I've compiled KoboDeluxe and I've gotten it to run by disabling sound.
I'm releasing this quick ipk for anyone that wants to mess around with it.
There is not icon installed yet, so you have to run from the console.
Here's how I run it:
# xrandr -s1; kobodl -nosound -fullscreen; xrandr -s 0
this effectively changes the screen resolution to 320x240 and starts the game in full screen. When you quit, it restores the screen to 640x480.
If you want to run this on the 6000, just :
# kobodl -nosound
By the way, the version number and description fields are not correct. I was in a hurry so I used the Control file from my xaos ipk. I'll create a more complete ipk once I get an icon and figure out if sound is possible.