After downloading it the first time from the M$ store, I got the game to work until I restarted my computer (from a forced Windows update). That bricked the files so they would not start, so I did the wizardry to get the dud files off my computer and free the space. Once all the space on my drive was free of all PSO2 files, I used the 3rd-party tweaker to redownload the game after failing to reinstall using Microsoft's crap (which made me micro-soft at the time).
The tweaker worked for awhile and I was able to successfully play the game even after restarting my computer a few times. I got no clue why or how PSO2 desired to play dead again, 'cause the game wouldn't launch after my most recent restart (not for any updates, mind you). So..... what gives? Why does this game refuse to run seemingly at random. I'm currently checking over the files using the tweaker and will try all the troubleshooting crap on there but this is waaaaaay too much BS for a game that should've "just work" via the M$ Store. I'll update after I get through the tweaker troubleshooting, but this post should be a reminder that whatever (if anything) y'all did to fix these problems did not work.
All I can say is... God d**n I wish this would just work: I'm loving the game and would really like to play it. Please?
EDIT: An update after I tried working with the tweaker: I got it to run again! For some reason, some of the games files decided to up and delete themselves. Thankfully the tweaker can remedy this problem fairly easily. I then had to fix all the .exe files, fix the file permissions, and re-run the M$ Store fix script from the Arks Layer peeps before the game decided to work again. This many steps and a 3rd-party, fan operated launcher should absolutely NOT be necessary for the game to function correctly. But, all that aside, I'm just thrilled I got it working again so I don't have to install the whole thing a third time.
As for the randomly self-deleted files, I have seen reports of others suffering the same glitch. It happens commonly on a computer restart and rarely while the computer is idle (which is totally random). My prime suspect is the DRM functionality of the M$ Store mucking with the game's file despite not needing to (it probably is the one deleting file for no good reason). Basically, if it wasn't for Microsoft and their DRM there would be virtually no problems with the game (since it works flawlessly in the Japanese client version).
As a final note for the devs: check for all integrations with the Microsoft Store. The problem certainly lies within those integrations (or is at least related). You will likely need to coordinate with Microsoft's team(s) heavily to find the problem (I figure you are already working with them, but the problem is 100% because of them and their storefront). The game runs almost perfectly on Xbox, so the issue is definitely how M$ (Microsoft) deals with the PC crowd. I also understand that you probably cannot jump to Steam or release a standalone launcher at this point due to their investment into the game. Just sad to see how they, the ones that invested heavily into your game, are also crippling it with bad practices and faulty code on their store.