I installed a x2.6 in my 1.6 box.
Worked first try. Booted Cromwell.
Flashed it whith Evox M8_16
Restart Works.
Insert boot disk for installing dashb. Works
Backed upp /C /E to my PC, ok.
Installed dash. Reboot, bios loads,
then nothing...
Now i can't boot from cd too..
Hmm.?

You are talking about Slayer's right. Is Evox M8_16 included in his ISO?
By the way did you save your EEPROM and BIOS also. Any conflicts with XBMC posibly.