x windows with touch screen as input device - isn't working

First, thanks for all the great information here. It makes learning a lot easier.

I have built a new version of Knoppix with some pieces removed, and have compiled and installed touch screen drivers. The image works fine on the laptop, I am able to plug the touch screen into the laptop, and use it (it's not perfect, since it's not actually on the laptop screen). The included calibration routines and test program work fine. The built in keyboard and touchpad also work as expected.

However, when I boot the same image on the target device, an AMD Geode based single board computer, it doesn't work. If I "cat" the driver and touch/move my finger around the touch screen, I see new data coming in, and the "driver file" grows. However, xwindows doesn't react based on this information. The calibration routines and test program still work just fine. The same configuration file is used for both systems, the touch screen is listed as a device in the file that Knoppix starts with and customizes on startup (XF86Config-4.in). A companion infrared keyboard/mouse combo works just fine.

All the details:
Laptop is a Intel based HP laptop Pavilion XT178.
Single board computer is AMD Geode based, it's a TC-10 from earthlcd.
The touch screen controller is an egalax or lilliput USB controller.
Knoppix started as 4.0.2, with some packages removed.

Any thoughts or ideas? Thanks in advance,

Paul