I have a slightly more elegant/simpler solution for getting windows store apps/games in LaunchBox:
⭕️ Copy and paste this into file explorer.
%windir%\explorer.exe shell:::{4234d49b-0245-4df3-b780-3893943456e1}
⭕️ What you have here is a list of all your installed games and apps INCLUDING from the Windows App Store. ⭕️ Right-clicking on an App store game gives you the option to "Create Shortcut". ⭕️ With this shortcut you can either get the direct address of the App without having to go through task manager, etc.
Or you can just place it in your LaunchBox/Games directory and point LB right at the short cut. Hope that helps! - Confirmed tested with 'Minecraft: Windows 10 Edition Beta' and 'Tennis in the Face'
Edit: didn't read the entire thread, the above is pretty much what was suggested by @DOS76, so credit to them.
How to add Windows Store games (e.g. Forza Apex)
in Troubleshooting
Posted
This one actually worked for me. Thank you.