Presumably Steam is installing games in ~/.local/share/Steam/ ; then you should manually go to ~/.local/share/Steam/SteamApps/common/Psichodelya via termianal ; list the files, there is a script called startup.sh. Run the script, it will ask you to change resolution via interactive input. Once you change it, it will run the game in correct resolution. Quit immedatelly, then run the game via shortuct or via steam just normally. It will run with the resolution that was last selected via script.

Presumably Steam is installing games in ~/.local/share/Steam/ ; then you should manually go to ~/.local/share/Steam/SteamApps/common/Psichodelya ; in that folder is a file called Controls.text, cat it. Due to Unity limitations on Linux, the start screen is not available (in which you change resolution and controls before starting the game), and these controls are fixed at this point in time. It's a very usefull reference for all 4 available control types.