Spaces in project names break AppImages

[hollunder]

$ ./Blind\ Wumpus\ World.AppImage 
find: ‘/tmp/.mount_Blind’: No such file or directory
find: ‘t0aEOf/usr/bin’: No such file or directory
/tmp/.mount_Blind t0aEOf/usr/bin//wrapper-love: line 5: /tmp/.mount_Blind: No such file or directory

If I replace the spaces with underscores the AppImage works as expected.

[pfirsich]

Amazingly this is solved simply by renaming the AppImage itself. Nothing inside the AppImage is broken.
It turns out this is a known issue: AppImage/AppImageKit#678
So as a "temporary" (issue was last updated in 2018 😞) workaround I will just strip spaces and print a message. Stripping instead of underscores is fine, I think, because title case for game names is pretty common.
I will keep this issue open, because I do not consider it fixed until the issue in AppImageKit has been resolved.