Error is: ./Dredmor-x86: error while loading shared libraries: libsteam_api.so: cannot open shared object file: No such file or directory This is not the Steam version of the game, Kubuntu 12.04LTS, 32 bit.
Actual problem: the correct file to run is Dredmor, not Dredmor-x86, Dredmor is not set to executable.
A) Yes, you should be running Dredmor, not dredmor-x86. B) Where did you get this from: Steam, Desura, or Humble? You said "not steam" so I think the problem is that a perms bit is set incorrectly.