i had different experience than your's on the mimo 740. i'm using debian-lenny on that but with evtouch driver (and no evdev).
1. Patch kernel 2.6.31 with displaylink support 2. Patch kernel 2.6.31 with ei touch screen support (attached e2itouch.diff) 3. Build kernel with attached .config 4. Use attached xorg.conf that uses evtouch AND disables xorg mouse support (otherwise all sort of artifacts on clicks will happen). 5. Use calibrate application in order to perform the touch screen calibration. Cut and paste the results and place them in your xorg.conf.
Note that armin76 reported (and I reproduced) and issue with the 'console' environment variable when being manually saved in u-boot The problem is that it doesn't get saved and always revers to the value '0xa0000'.
We found the issue and will be fixed soon with newer version of U-Boot.