Install Steam
login
|
language
简体中文 (Simplified Chinese)
繁體中文 (Traditional Chinese)
日本語 (Japanese)
한국어 (Korean)
ไทย (Thai)
Български (Bulgarian)
Čeština (Czech)
Dansk (Danish)
Deutsch (German)
Español - España (Spanish - Spain)
Español - Latinoamérica (Spanish - Latin America)
Ελληνικά (Greek)
Français (French)
Italiano (Italian)
Bahasa Indonesia (Indonesian)
Magyar (Hungarian)
Nederlands (Dutch)
Norsk (Norwegian)
Polski (Polish)
Português (Portuguese - Portugal)
Português - Brasil (Portuguese - Brazil)
Română (Romanian)
Русский (Russian)
Suomi (Finnish)
Svenska (Swedish)
Türkçe (Turkish)
Tiếng Việt (Vietnamese)
Українська (Ukrainian)
Report a translation problem
Whether you allow said scan or not, in your Proton case certainly it won't find any, and it upon doing such simply goes on to start the game -- which for you seemingly fails but not then due to any of the foregoing.
GTA4 is not a Steam Play supported title; you've had to enable "Enable Steam Play for all other titles" in Settings -> Compatibility. For any such title you are on your own; for most such titles you may expect badness; for specifically GTA4 you can expect things and most specifically the RGL to be not broken as an exception.
That said, I just tried GTA IV on current Steam Play on an Ubuntu 22.04 base and for me it currently starts (although it's unplayably choppy). I.e., dunno what would be your current issue on Arch and your hardware, but it's in any case not to do with that GFWL savegame stuff.
Careful that also a downgraded version of GTA4 is going to have issues with FPS over 30; over 60 most importantly. For the current "The Complete Edition" the advise is installing FusionFix, but if you downgrade you're going to have to take care of things yourself.
For an incomplete list of issues see https://github.com/GTAmodding/GTAIV-Issues-List/issues/112. All are as applicable to a downgraded GFWL-edition as to the current RGL-edition (and to the Xbox One, Series, PS4, PS5, ...)