diff --git a/bin/winapps b/bin/winapps
index 6890ae7..b591e03 100755
--- a/bin/winapps
+++ b/bin/winapps
@@ -1,188 +1,329 @@
 #!/usr/bin/env bash
 
-if [ ! -f "$HOME/.config/winapps/winapps.conf" ] && [ ! -f "$HOME/.winapps" ]; then
-	echo "You need to create a ~/.config/winapps/winapps.conf configuration. Exiting..."
-	exit
-fi
+### GLOBAL CONSTANTS ###
+# ANSI ESCAPE SEQUENCES
+readonly ERROR_TEXT="\033[1;41;37m" # Bold + White + Red Background
+readonly CLEAR_TEXT="\033[0m"       # Clear
 
-DIR="$(dirname "$(readlink -f "$0")")"
-RUN="$(date)-$RANDOM"
+# ERROR CODES
+readonly EC_MISSING_CONFIG=1
+readonly EC_MISSING_FREERDP=2
+readonly EC_NOT_IN_GROUP=3
+readonly EC_VM_NOT_RUNNING=4
+readonly EC_VM_NO_IP=5
+readonly EC_VM_BAD_PORT=6
+readonly EC_UNSUPPORTED_APP=7
 
-if [ ! -d "$HOME/.local/share/winapps" ]; then
-	mkdir -p "$HOME/.local/share/winapps"
-fi
+# PATHS
+readonly APPDATA_PATH="${HOME}/.local/share/winapps"
+readonly SYS_APP_PATH="/usr/local/share/winapps"
+readonly LASTRUN_PATH="${APPDATA_PATH}/lastrun"
+readonly LOG_PATH="${APPDATA_PATH}/winapps.log"
+readonly CONFIG_PATH="${HOME}/.config/winapps/winapps.conf"
+# shellcheck disable=SC2155 # Silence warnings regarding masking return values through simultaneous declaration and assignment.
+readonly SCRIPT_DIR_PATH="$(cd "$(dirname "${BASH_SOURCE[0]}")" &>/dev/null && pwd)"
 
+# OTHER
+readonly VM_NAME="RDPWindows"
+readonly RDP_PORT=3389
+# shellcheck disable=SC2155 # Silence warnings regarding masking return values through simultaneous declaration and assignment.
+readonly RUN="$(date)-${RANDOM}"
+
+### GLOBAL VARIABLES ###
+# WINAPPS CONFIGURATION FILE
+RDP_USER=""
+RDP_PASS=""
+RDP_DOMAIN=""
+RDP_IP=""
+RDP_FLAGS=""
+FREERDP_COMMAND=""
 RDP_SCALE=100
+MULTIMON="false"
+DEBUG="true"
+MULTI_FLAG=""
 
-if [ -f "$HOME/.config/winapps/winapps.conf" ]; then
-	# shellcheck source=/dev/null
-	. "$HOME/.config/winapps/winapps.conf"
-else
-	# shellcheck source=/dev/null
-	. "$HOME/.winapps"
-fi
+### FUNCTIONS ###
+# Name: 'waThrowExit'
+# Role: Throw an error message and exit the script.
+function waThrowExit() {
+	# Declare variables.
+	local ERR_CODE="$1"
 
+	# Throw error.
+	case "$ERR_CODE" in
+	"$EC_MISSING_CONFIG")
+		# Missing WinApps configuration file.
+		dprint "ERROR: MISSING WINAPPS CONFIGURATION FILE. EXITING."
+		echo -e "${ERROR_TEXT}ERROR: MISSING WINAPPS CONFIGURATION FILE.${CLEAR_TEXT}"
+		echo "Please create a WinApps configuration file at '${CONFIG_PATH}'".
+		;;
+	"$EC_MISSING_FREERDP")
+		dprint "ERROR: FREERDP VERSION 3 IS NOT INSTALLED. EXITING."
+		echo -e "${ERROR_TEXT}ERROR: FREERDP VERSION 3 IS NOT INSTALLED.${CLEAR_TEXT}"
+		;;
+	"$EC_NOT_IN_GROUP")
+		dprint "ERROR: USER NOT PART OF REQUIRED GROUPS. EXITING."
+		echo -e "${ERROR_TEXT}ERROR: USER NOT PART OF REQUIRED GROUPS.${CLEAR_TEXT}"
+		echo "Please run:"
+		echo "  sudo usermod -a -G libvirt $(whoami)"
+		echo "  sudo usermod -a -G kvm $(whoami)"
+		;;
+	"$EC_VM_NOT_RUNNING")
+		dprint "ERROR: VM NOT RUNNING. EXITING."
+		echo -e "${ERROR_TEXT}ERROR: VM NOT RUNNING.${CLEAR_TEXT}"
+		echo "Please ensure the Windows VM is powered on."
+		;;
+	"$EC_VM_NO_IP")
+		dprint "ERROR: VM UNREACHABLE. EXITING."
+		echo -e "${ERROR_TEXT}ERROR: VM UNREACHABLE.${CLEAR_TEXT}"
+		echo "Please ensure the Windows VM is assigned an IP address."
+		;;
+	"$EC_VM_BAD_PORT")
+		dprint "ERROR: RDP PORT CLOSED. EXITING."
+		echo -e "${ERROR_TEXT}ERROR: RDP PORT CLOSED.${CLEAR_TEXT}"
+		echo "Please ensure Remote Desktop is correctly configured on the Windows VM."
+		;;
+	"$EC_UNSUPPORTED_APP")
+		dprint "ERROR: APPLICATION NOT FOUND. EXITING."
+		echo -e "${ERROR_TEXT}ERROR: APPLICATION NOT FOUND.${CLEAR_TEXT}"
+		echo "Please ensure the program is correctly configured as an officially supported application."
+		;;
+	esac
+
+	# Provide generic advice.
+	echo "Check the WinApps project README for more information."
+
+	# Terminate the script.
+	echo "Exiting with status '${ERR_CODE}'."
+	exit "$ERR_CODE"
+}
+
+# Name: 'dprint'
+# Role: Conditionally print debug messages to a log file, creating it if it does not exist.
 function dprint() {
-	if [ "$DEBUG" = "true" ]; then
-		echo "[$RUN] $1" >>"$HOME/.local/share/winapps/winapps.log"
+	[ "$DEBUG" = "true" ] && echo "[$RUN] $1" >>"$LOG_PATH"
+}
+
+# Name: 'waLoadConfig'
+# Role: Load the variables within the WinApps configuration file.
+function waLoadConfig() {
+	# Load WinApps configuration file.
+	if [ -f "$CONFIG_PATH" ]; then
+		# shellcheck source=/dev/null # Exclude WinApps configuration file from being checked by ShellCheck.
+		source "$CONFIG_PATH"
+	else
+		waThrowExit $EC_MISSING_CONFIG
+	fi
+
+	# Update 'MULTI_FLAG' based on 'MULTIMON'.
+	MULTI_FLAG=$([[ $MULTIMON == "true" ]] && echo "/multimon" || echo "+span")
+
+	# Append additional flags or parameters to FreeRDP.
+	[[ -n $RDP_FLAGS ]] && FREERDP_COMMAND="${FREERDP_COMMAND} ${RDP_FLAGS}"
+}
+
+# Name: 'waLastRun'
+# Role: Determine the last time this script was run.
+function waLastRun() {
+	# Declare variables.
+	local LAST_RUN_UNIX_TIME=0
+	local CURR_RUN_UNIX_TIME=0
+
+	# Store the time this script was run last as a unix timestamp.
+	if [ -f "$LASTRUN_PATH" ]; then
+		LAST_RUN_UNIX_TIME=$(stat -t -c %Y "$LASTRUN_PATH")
+		dprint "LAST_RUN: ${LAST_RUN_UNIX_TIME}"
+	fi
+
+	# Update the file modification time with the current time.
+	touch "$LASTRUN_PATH"
+	CURR_RUN_UNIX_TIME=$(stat -t -c %Y "$LASTRUN_PATH")
+	dprint "THIS_RUN: ${CURR_RUN_UNIX_TIME}"
+}
+
+function waGetFreeRDPCommand() {
+	# Attempt to set a FreeRDP command if the command variable is empty.
+	if [ -z "$FREERDP_COMMAND" ]; then
+		# Check for 'xfreerdp'.
+		if command -v xfreerdp &>/dev/null; then
+			# Check FreeRDP major version is 3 or greater.
+			FREERDP_MAJOR_VERSION=$(xfreerdp --version | head -n 1 | grep -o -m 1 '\b[0-9]\S*' | cut -d'.' -f1)
+			if [[ $FREERDP_MAJOR_VERSION =~ ^[0-9]+$ ]] && ((FREERDP_MAJOR_VERSION >= 3)); then
+				FREERDP_COMMAND="xfreerdp"
+			fi
+		# Check for 'xfreerdp3'.
+		elif command -v xfreerdp3 &>/dev/null; then
+			# Check FreeRDP major version is 3 or greater.
+			FREERDP_MAJOR_VERSION=$(xfreerdp3 --version | head -n 1 | grep -o -m 1 '\b[0-9]\S*' | cut -d'.' -f1)
+			if [[ $FREERDP_MAJOR_VERSION =~ ^[0-9]+$ ]] && ((FREERDP_MAJOR_VERSION >= 3)); then
+				FREERDP_COMMAND="xfreerdp3"
+			fi
+		fi
+
+		# Check for FreeRDP Flatpak (fallback option).
+		if [ -z "$FREERDP_COMMAND" ]; then
+			if command -v flatpak &>/dev/null; then
+				if flatpak list --columns=application | grep -q "^com.freerdp.FreeRDP$"; then
+					# Check FreeRDP major version is 3 or greater.
+					FREERDP_MAJOR_VERSION=$(flatpak list --columns=application,version | grep "^com.freerdp.FreeRDP" | awk '{print $2}' | cut -d'.' -f1)
+					if [[ $FREERDP_MAJOR_VERSION =~ ^[0-9]+$ ]] && ((FREERDP_MAJOR_VERSION >= 3)); then
+						FREERDP_COMMAND="flatpak run --command=xfreerdp com.freerdp.FreeRDP"
+					fi
+				fi
+			fi
+		fi
+	fi
+
+	if command -v "$FREERDP_COMMAND" &>/dev/null || [ "$FREERDP_COMMAND" = "flatpak run --command=xfreerdp com.freerdp.FreeRDP" ]; then
+		dprint "Using FreeRDP command '${FREERDP_COMMAND}'."
+	else
+		waThrowExit "$EC_MISSING_FREERDP"
 	fi
 }
 
+# Name: 'waCheckGroupMembership'
+# Role: Ensures the current user is part of the required groups.
+function waCheckGroupMembership() {
+	# Identify groups the current user belongs to.
+	# shellcheck disable=SC2155 # Silence warnings regarding masking return values through simultaneous declaration and assignment.
+	local USER_GROUPS=$(groups "$(whoami)")
+
+	if ! (echo "$USER_GROUPS" | grep -q -E "\blibvirt\b") || ! (echo "$USER_GROUPS" | grep -q -E "\bkvm\b"); then
+		waThrowExit "$EC_NOT_IN_GROUP"
+	fi
+}
+
+# Name: 'waCheckVMRunning'
+# Role: Throw an error if the Windows VM is not running.
+function waCheckVMRunning() {
+	! virsh list --state-running --name | grep -q "^${VM_NAME}$" && waThrowExit "$EC_VM_NOT_RUNNING"
+}
+
+# Name: 'waCheckVMContactable'
+# Role: Assesses whether the Windows VM can be contacted.
+function waCheckVMContactable() {
+	# Declare variables.
+	local VM_MAC="" # Stores the MAC address of the Windows VM.
+
+	# Obtain Windows VM IP Address
+	if [ -z "$RDP_IP" ]; then
+		VM_MAC=$(virsh domiflist "$VM_NAME" | grep -oE "([0-9A-Fa-f]{2}[:-]){5}([0-9A-Fa-f]{2})") # VM MAC address.
+		RDP_IP=$(arp -n | grep "$VM_MAC" | grep -oE "([0-9]{1,3}\.){3}[0-9]{1,3}")                # VM IP address.
+		[ -z "$RDP_IP" ] && waThrowExit "$EC_VM_NO_IP"
+	fi
+
+	# Check for an open RDP port.
+	timeout 5 nc -z "$RDP_IP" "$RDP_PORT" &>/dev/null || waThrowExit "$EC_VM_BAD_PORT"
+}
+
+function waRunCommand() {
+	# Declare variables.
+	local ICON=""
+	local FILE_PATH=""
+
+	# Run option.
+	if [ "$1" = "windows" ]; then
+		# Open Windows VM.
+		dprint "WINDOWS"
+		$FREERDP_COMMAND \
+			/d:"$RDP_DOMAIN" \
+			/u:"$RDP_USER" \
+			/p:"$RDP_PASS" \
+			/scale:"$RDP_SCALE" \
+			+dynamic-resolution \
+			+auto-reconnect \
+			+home-drive \
+			/wm-class:"Microsoft Windows" \
+			/v:"$RDP_IP" &>/dev/null &
+	elif [ "$1" = "manual" ]; then
+		# Open specified application.
+		dprint "MANUAL: ${2}"
+		$FREERDP_COMMAND \
+			/cert:tofu \
+			/d:"$RDP_DOMAIN" \
+			/u:"$RDP_USER" \
+			/p:"$RDP_PASS" \
+			/scale:"$RDP_SCALE" \
+			+auto-reconnect \
+			+clipboard \
+			+home-drive \
+			-wallpaper \
+			+dynamic-resolution \
+			"$MULTI_FLAG" \
+			/app:program:"$2" \
+			/v:"$RDP_IP" &>/dev/null &
+	else
+		# Script summoned from right-click menu with officially supported application name plus/minus a file path.
+		if [ -e "${SCRIPT_DIR_PATH}/../apps/${1}/info" ]; then
+			# shellcheck source=/dev/null # Exclude this file from being checked by ShellCheck.
+			source "${SCRIPT_DIR_PATH}/../apps/${1}/info"
+			ICON="${SCRIPT_DIR_PATH}/../apps/${1}/icon.svg"
+		elif [ -e "${APPDATA_PATH}/apps/${1}/info" ]; then
+			# shellcheck source=/dev/null # Exclude this file from being checked by ShellCheck.
+			source "${APPDATA_PATH}/apps/${1}/info"
+			ICON="${APPDATA_PATH}/apps/${1}/icon.svg"
+		elif [ -e "${SYS_APP_PATH}/apps/${1}/info" ]; then
+			# shellcheck source=/dev/null # Exclude this file from being checked by ShellCheck.
+			source "${SYS_APP_PATH}/apps/${1}/info"
+			ICON="${SYS_APP_PATH}/apps/${1}/icon.svg"
+		else
+			waThrowExit "$EC_UNSUPPORTED_APP"
+		fi
+
+		# Check if a file path was specified, and pass this to the application.
+		if [ -z "$2" ]; then
+			# No file path specified.
+			$FREERDP_COMMAND \
+				/d:"$RDP_DOMAIN" \
+				/u:"$RDP_USER" \
+				/p:"$RDP_PASS" \
+				/scale:"$RDP_SCALE" \
+				+auto-reconnect \
+				+clipboard \
+				+home-drive \
+				-wallpaper \
+				+dynamic-resolution \
+				"$MULTI_FLAG" \
+				/wm-class:"$FULL_NAME" \
+				/app:program:"$WIN_EXECUTABLE",icon:"$ICON",name:"$FULL_NAME" \
+				/v:"$RDP_IP" &>/dev/null &
+		else
+			# Convert path from UNIX to Windows style.
+			FILE_PATH=$(echo "$2" | sed 's|'"${HOME}"'|\\\\tsclient\\home|;s|/|\\|g;s|\\|\\\\|g')
+			dprint "UNIX_FILE_PATH: ${2}"
+			dprint "WINDOWS_FILE_PATH: ${FILE_PATH}"
+
+			$FREERDP_COMMAND \
+				/cert:tofu \
+				/d:"$RDP_DOMAIN" \
+				/u:"$RDP_USER" \
+				/p:"$RDP_PASS" \
+				/scale:"$RDP_SCALE" \
+				+auto-reconnect \
+				+clipboard \
+				+home-drive \
+				-wallpaper \
+				+dynamic-resolution \
+				"$MULTI_FLAG" \
+				/wm-class:"$FULL_NAME" \
+				/app:program:"$WIN_EXECUTABLE",icon:"$ICON",name:$"FULL_NAME",cmd:\""$FILE_PATH"\" \
+				/v:"$RDP_IP" &>/dev/null &
+		fi
+	fi
+}
+
+### MAIN LOGIC ###
+#set -x # Enable for debugging.
 dprint "START"
-
-if [ -f "$HOME/.local/share/winapps/run" ]; then
-	LAST_RAN=$(stat -t -c %Y "$HOME/.local/share/winapps/run")
-	dprint "LAST_RAN:${LAST_RAN}"
-	touch "$HOME/.local/share/winapps/run"
-	THIS_RUN=$(stat -t -c %Y "$HOME/.local/share/winapps/run")
-	dprint "THIS_RUN:$THIS_RUN"
-	if ((THIS_RUN - LAST_RAN < 2)); then
-		exit
-	fi
-else
-	touch "$HOME/.local/share/winapps/run"
-fi
-
-if [ -z "${FREERDP_COMMAND}" ]; then
-	if command -v xfreerdp &>/dev/null; then
-		FREERDP_COMMAND="xfreerdp"
-	elif command -v xfreerdp3 &>/dev/null; then
-		FREERDP_COMMAND="xfreerdp3"
-	fi
-elif command -v "$FREERDP_COMMAND" &>/dev/null; then
-	dprint "Using custom freerdp command $FREERDP_COMMAND"
-else
-	echo "You have supplied a custom FreeRDP command, but the command is not available."
-	exit
-fi
-
-if [ -z "$RDP_IP" ]; then
-	if groups | grep -vq libvirt; then
-		echo "You are not a member of the libvirt group. Run the below then reboot."
-		echo "  sudo usermod -a -G libvirt $(whoami)"
-		echo "  sudo usermod -a -G kvm $(whoami)"
-		exit
-	fi
-	if ! virsh list --state-running --name | grep -q '^RDPWindows$'; then
-		echo "RDPWindows is not running. Please run:"
-		echo "  virsh start RDPWindows"
-		exit
-	fi
-	RDP_IP=$(virsh net-dhcp-leases default | grep "RDPWindows" | grep -oE '([0-9]{1,3}\.){3}[0-9]{1,3}')
-fi
-
-dprint "1:$1"
-dprint "2:$2"
-# this is just for debug logging anyways
-# shellcheck disable=SC2145
-dprint "@:${@}"
-
-MULTI_FLAG="+span"
-if [ "$MULTIMON" = "true" ]; then
-	MULTI_FLAG="/multimon"
-fi
-
-# Append additional flags or parameters to FreeRDP
-if [[ -n $RDP_FLAGS ]]; then
-	FREERDP_COMMAND="$FREERDP_COMMAND $RDP_FLAGS"
-fi
-
-if [ "$1" = "windows" ]; then
-	# Open Virtual Machine
-	dprint "WINDOWS"
-	COMMAND=(
-		"${FREERDP_COMMAND}"
-		"/d:${RDP_DOMAIN}"
-		"/u:${RDP_USER}"
-		"/p:${RDP_PASS}"
-		"/scale:${RDP_SCALE}"
-		"+dynamic-resolution"
-		"+auto-reconnect"
-		"+home-drive"
-		'/wm-class:"Microsoft Windows"'
-		"/v:${RDP_IP}"
-	)
-	# Run the command in the background, redirecting both stdout and stderr to /dev/null
-	"${COMMAND[@]}" 1>/dev/null 2>&1 &
-elif [ "$1" = "manual" ]; then
-	# Open Specified Application
-	dprint "MANUAL:${2}"
-	COMMAND=(
-		"${FREERDP_COMMAND}"
-		"/d:${RDP_DOMAIN}"
-		"/u:${RDP_USER}"
-		"/p:${RDP_PASS}"
-		"/scale:${RDP_SCALE}"
-		"+auto-reconnect"
-		"+home-drive"
-		"+dynamic-resolution"
-		"${MULTI_FLAG}"
-		"/app:program:${2}"
-		"/v:${RDP_IP}"
-	)
-	# Run the command in the background, redirecting both stdout and stderr to /dev/null
-	"${COMMAND[@]}" 1>/dev/null 2>&1 &
-elif [ "$1" != "install" ]; then
-	dprint "DIR:${DIR}"
-	if [ -e "${DIR}/../apps/$1/info" ]; then
-		# shellcheck disable=SC1090
-		. "${DIR}/../apps/$1/info"
-		ICON="${DIR}/../apps/$1/icon.svg"
-	elif [ -e "$HOME/.local/share/winapps/apps/$1/info" ]; then
-		# shellcheck disable=SC1090
-		. "$HOME/.local/share/winapps/apps/$1/info"
-		ICON="$HOME/.local/share/winapps/apps/$1/icon.svg"
-	elif [ -e "/usr/local/share/winapps/apps/$1/info" ]; then
-		# shellcheck disable=SC1090
-		. "/usr/local/share/winapps/apps/$1/info"
-		ICON="/usr/local/share/winapps/apps/$1/icon.svg"
-	else
-		echo "You need to run 'installer.sh' first."
-		exit 1
-	fi
-	if [ -n "$2" ]; then
-		dprint "HOME:$HOME"
-		FILE=$(echo "$2" | sed 's|'"$HOME"'|\\\\tsclient\\home|;s|/|\\|g;s|\\|\\\\|g')
-		dprint "FILE:${FILE}"
-		# shellcheck disable=SC2140
-		COMMAND=(
-			"${FREERDP_COMMAND}"
-			"/d:${RDP_DOMAIN}"
-			"/u:${RDP_USER}"
-			"/p:${RDP_PASS}"
-			"/scale:${RDP_SCALE}"
-			"+auto-reconnect"
-			"+clipboard"
-			"+home-drive"
-			"-wallpaper"
-			"+dynamic-resolution"
-			"${MULTI_FLAG}"
-			"/wm-class:${FULL_NAME}"
-			"/app:program:${WIN_EXECUTABLE},icon:${ICON},name:${FULL_NAME},cmd:\"${FILE}\""
-			"/v:${RDP_IP}"
-		)
-		# Run the command in the background, redirecting both stdout and stderr to /dev/null
-		echo "${COMMAND[@]}" #1>/dev/null 2>&1 &
-	else
-		COMMAND=(
-			"${FREERDP_COMMAND}"
-			"/d:${RDP_DOMAIN}"
-			"/u:${RDP_USER}"
-			"/p:${RDP_PASS}"
-			"/scale:${RDP_SCALE}"
-			"+auto-reconnect"
-			"+clipboard"
-			"+home-drive"
-			"-wallpaper"
-			"+dynamic-resolution"
-			"${MULTI_FLAG}"
-			"/wm-class:${FULL_NAME}"
-			"/app:program:${WIN_EXECUTABLE},icon:${ICON},name:${FULL_NAME}"
-			"/v:${RDP_IP}"
-		)
-		# Run the command in the background, redirecting both stdout and stderr to /dev/null
-		"${COMMAND[@]}" 1>/dev/null 2>&1 &
-	fi
-fi
-
+dprint "SCRIPT_DIR: ${SCRIPT_DIR_PATH}"
+dprint "SCRIPT_ARGS: ${*}"
+dprint "HOME_DIR: ${HOME}"
+mkdir -p "$APPDATA_PATH"
+waLastRun
+waLoadConfig
+waGetFreeRDPCommand
+waCheckGroupMembership
+waCheckVMRunning
+waCheckVMContactable
+waRunCommand "$@"
 dprint "END"
diff --git a/installer.sh b/installer.sh
index 32973f4..ebf1913 100755
--- a/installer.sh
+++ b/installer.sh
@@ -1,5 +1,5 @@
 #!/usr/bin/env bash
-# shellcheck disable=SC2034              # Silence warnings regarding unused variables globally.
+# shellcheck disable=SC2034           # Silence warnings regarding unused variables globally.
 
 ### GLOBAL CONSTANTS ###
 # ANSI ESCAPE SEQUENCES