German and demo version support broken?

[laenion]

When trying to use the German disc version as a data dir with a current git checkout the game fails with the following message:

DETHRACE_ROOT_DIR: /media/cdrom/
[INFO] Harness_DetectGameMode "Carmageddon"
[WARN] SoundService stubbed
[WARN] NetService stubbed
dprintf: FATAL ERROR: This .exe must have KEYBOARD.COK in the DATA folder.
FATAL ERROR: This .exe must have KEYBOARD.COK in the DATA folder.

The file indeed doesn't seem to be available, also when installing the game. On the other hand I can see variable names with GERMAN in their name, so I assume the version should be supported?

(Something may be wrong with the detection mechanism in general, or I'm doing something completely wrong: I also couldn't start the Original Carmageddon demo or the Splat Pack demo linked from the GitHub page...)