If you grab a daily build the engine should be enabled (note that since it is not supported yet things might still break). Note that there is currently no translation, though.

The fonts/ directory is supposed to be inside the game data directory, not themes/ (the engine looks for files relative to the game data directory).

I have noticed this as well and from what I remember I could fairly easily reproduce it on Windows but not Linux. I plan on having a look at this when I find some time.

In case anybody else is wondering, the game does support loading/saving via the the GMM (CTRL-F5) just fine.

Nitrus/SimSaw: Any update on this guys?