I just recently got a hold of a UDC card, and I'm just now getting around to testing it.
I have only been able to test it with a standard Apple 5.25 drive. Instead of regularly booting like it should, It makes a loud revving noise and then comes up with the following message:
"Error Number: 40
Boot error. Please check your
diskette and disk drive."
So far I have checked very minor things and have come up with no clues.
Pictures coming soon...