things i dnt like about MS
i bought many arcade games on xbox from 2009 - 2012 and the big issue is i need xbox live gold to play them even if i want to play alone id have to pay £$0 a year jsut to do that, microsoft consoles are shit, if your gonna get a console get a switch or a ps4.

only thing i use from MS is windows thats it, until games can run easily on linux as on windows i lstick with windows until that day comes

You sure on that/is that for 360 as well? I ask as I believe I have several such games and they run without live in SP mode.

(Also I just got an XB1 and it seems fine....the ability to surf more websites than on 360 without crashes is welcome, as is the ability to suspend/resume games and apps so I don't have to fully stop a game/app to do something else)

Side rant: I dislike how they removed the indie games many months back on 360.....some looked decent for a buck or two.

You're just spreading falsehoods now.

There are no single player games on Xbox that need an Xbox Live Gold subscription if you purchased the game. The only thing you need Gold for is multiplayer or to play the bonus Games with Gold games that are part of the subscription- those are not purchases though, they are more like rentals that you have access to any time you have a Gold subscription- sort of like the Humble vault games anytime you have a Humble subscription. Even that only applies to Xbox One Games with Gold, the Xbox 360 games are classed as purchases and work even when your subscription lapses. Or to put it another way, it works exactly like on a PS4, there is no difference. I have both consoles, plus 360 and PS3, it works the same way on all of them. Wait, you are signed into your account on your Xbox when you try to play right? You do need your console signed in to your profile...it doesn't have to be online, but does need to be signed in locally just the same.

As for the OP, I don't see what this specifically has to do with Game Pass. The problems with not being able to access files applies to any MS Store game regardless of whether it's bought or played using Game Pass. You would be having this exact same issue regardless of whether you purchased the game or played it using rental...it's the same code. Also on a side note, can't you get the saves from the cloud? Anyway, there is a way through hidden settings to get access to things, but it is a pain in the ass and the system should be overhauled for sure, there's no denying that. Anyway, this may help get access and find things if you want to try and fix it yourself: https://www.auslogics.com/en/articles/where-are-games-from-microsoft-store-saved-on-windows-10/

On the other hand, a broken game isn't totally the problem of the platform holder. Other games work from the Win 10 store despite not being able to access files yourself. If a game is bugged and broken on Steam or PlayStation or even on GoG...no one expects Steam or Sony or GoG to fix it, they blame the developer or publisher and demand they fix it. They are the ones that have to fix the issues with the game on that platform if they want to sell it there.