@Plagman Maybe you want to label this "CW" too?
The Pinball FX2 issue (#346) is labeled CW, and this is basically the same issue with regards to the Steam2.dll.so file that's missing.
Looks like this issue needs some updating. Game runs on the lbandy beta branch fine, but only up to Proton 4.11-13. Later versions can't launch the game at all.
Hello @Sanaki, please add PROTON_LOG=1 %command% to the game's launch options, reproduce the issue you're seeing with newer Proton, and attach the generated $HOME/steam-$APPID.log to this issue report as a file. (Proton logs compress well if needed.) Also, please copy your system information from Steam (Steam -> Help -> System Information) and put it in a gist, then include a link to the gist in this issue report.
I actually need to retract that report. In the process of pulling logs, I did the responsible thing and nuked my prefix... at which point the non-beta worked on experimental fine. Seems the prior prefix did not migrate successfully.
Compatibility Report
System Information
I confirm:
I've attached the relevant portion of the Proton log.
steam-255370.log
Symptoms
The game fails to launch as Proton cannot find Steam2.dll.so to substitute for Steam2.dll - which is used by KickBeat.
Reproduction
Install the game through Steam and try launching it.