small succes: with the translate from 10.5.2 the system boots into 10.5.3 correctly.

some issues though:
- "dsmos.kext cannot be used" message (fixed by reinstalling with kext helper)
- lost QE/CI (broken even after reinstalling with nvinstaller, YMMV)
- sound lost (will most probably be fixed by running applehdapatcher again)

also I might add: my main 10.5.2 install froze in the middle of the installation, so I had to get into my backup 10.5.2 install to do the update.