Hello @sifiro, it might be interesting to test how the game behaves with its launch options set to PROTON_SET_GAME_DRIVE=1 %command% and backing out your workaround.
Okay, It looks like it works as expected. (Now loads from virtual S drive)
Info.txt
So... PROTON_SET_GAME_DRIVE huh? Good to know.
Thinking about it, I totally forgot Steam allows the use of multiple drives so It could be another way of workaround.
But yeah, Great solution.
PROTON_SET_GAME_DRIVEx1 2022-07PROTON_SET_GAME_DRIVE=1x1 2022-07PROTON_SET_GAME_DRIVE=1 %command%x1 2022-07
Compatibility Report
System Information
I confirm:
Symptoms
The game deletes dots from directorypath when It tries to load files.
For example, when It tries to read "$HOME/.local/share/Steam/steamapps/common/Littlewitch Romanesque Editio Regia/K49.dat", try to read "$HOME/local/share/Steam/steamapps/common/Littlewitch Romanesque Editio Regia/K49.dat" and of course. that directory doesn't exist or If it exists probably doesn't have the files expected by the game (but if you make a symbolic link to .local to local o try to move the game files to that directory)
A Workaround, It could be make a symbolic link from $HOME/.local to $HOME/local.
But It could be appreciated an out-of-the-box solution (especially for SteamDeck) as for example some kind of virtual folder only recognized by Proton (or maybe make a symbolic link from .local/steam to drive_c/Program Files/Steam and run from there.)
(Of Course, It's read from Z:\home\$USER, I am just simplifying the directory)
I attached the info file generated by the game which shows from where reads the files.
Info.txt
I highlight this section:
Reproduction