This post is to increase awareness about the details of buying this game through the Microsoft Store, which I personally have never done for any game or product that I know of except this one.
1. The game's install location will be locked behind an OS security scheme in a hidden folder in your x64 program files folder. In order to access the game for mods or other normal gamer activity like linking mouse profiles, adding to game libraries etc, you'll need to take ownership of this entire hidden folder through advanced security settings - which probably has non-zero ramifications for system security.
2. If you have never used the Xbox services on your PC for anything, then you will be repeatedly hounded to create a gamertag with a large popup Windows 10 panel that obscures the main menu - at every start of the game and each time after leaving the settings screen in the main menu area.
3. If you begin a game without creating an Xbox Live gamertag (in case the idea doesn't interest you even a little bit) and then later decide it's harmless to do so, and you do so, then your savegame(s) will disappear. They won't be in a folder to find and relocate to a new folder, they won't be in some oblivion in a cloud, they will cease to exist for your purposes. This may also happen if you decide to change your gamertag at some point. Since at least 2012 we PC gamers have been enjoying this feature. **EDIT: If you just sign out of Xbox Live your savegame(s) will return, along with the panel. Call it meta-dystopian.**
4. If you decide that all this is really great deployment of the Live service and is well designed and everything, but you just feel it's not a good fit and try to request a refund from Microsoft, then be prepared to deal with that process, which is all I will say about it as I haven't attempted this myself. I'd rather just accept the sale price of $44 for this imperfect version - I mean after all it did presumably go to Obsidian even though the software has been arbitrarily mangled by a third party who knows little to nothing about PC games deployment despite being in operation for some number of years.
So, this isn't a cautionary tale or a critique of a large distributor, or a blasting of the Xbox Live Services PC team, nor even an angry rant about a situation that seems illogical or asinine or pathetic - it's just a friendly list of items I've observed in my experiment with Xbox Live and this lovely game, and it is lovely thank you Obsidian - for everything.
Now for some obscura: the Book of the Machines was written by frightened villagers in a desolate waste! Do not be led astray!