OK; after i installed AISuite III from the CD, i had again the long boot time and the last error message from my first post here.
I checked the AMDA00 device in the hardware manager and it had the triangle again, but i could disable/enable the device and it worked.
I then went to the bin-folder and installed the AMDA00 driver from this location and after a reboot AMDA00 works fine.
So it looks like version 1.00.50 of the AISuite III comes with a faulty AMDA00 driver that fails to load because of a timing problem.
The driver in the bin-folder on the CD is obviously fixed regarding this issue.
The "\Driver\WUDFRd für das Gerät ACPI\PNP0A0A\2&daba3ff&1" - error is still there, but according to MS, this is a timing issue and can be ignored:
http://support.microsoft.com/kb/974720/en-usThank you for the help to fix the problem !
rgds, Enrico