Here's one of my old Dingux porting projects: ZDoom. It's based on the latest OpenAL branch (Oct 23, 2013)

Installing
* Install the OPK;
* copy your WAD files to your device;
* add the ".bin" extension to your WADs (doom.wad -> doom.wad.bin);
* run ZDoom and then select your desired WAD to play.

Settings
* You can set most of the configurations through the options menu. If you want more advanced settings, edit the /media/data/local/home/.config/zdoom/zdoom.ini file.

Known Issues
* There's no music.

TODO
* Enable midi music playback;
* translate pc keys name to GCW-Zero buttons name (escape -> select, enter -> start, etc);
* adjust the save screen to allow enter some unique label (a timestamp, maybe);
* full automate the building process.

Download
ZDoom.opk (2014-06-15) : http://www.mediafire.com/download/o9g7gxkojnvl56y/zdoom.opk

Note: this is a development build, so there's a lot of things to do.
You can follow my code commits here: https://github.com/Shin-NiL/zdoom/commits/gcw0


Thread : http://boards.dingoonity.org/gcw-development/zdoom/