Help! Cannot install WebAS Test Drive 6.20

I had V6.10 installed and removed it. I am now attemping an install of 6.20. It runs to the point where it has requested info from DATA CDs 1 and 2, and has returned to the Kernel CD. At some point along that path, I see a message that says "Installation of DB Server finished successfully".

However, I am getting this serious installation error:

Error: ADADBREGISTER_IND_ADA ExecuteCheck 2 223

Exit code from C:\sapdb\programs\pgm\dbmcli.exe: 2.

Error: ADADBREGISTER_IND_ADA InternalInstallationDo 2 223

Phase failed.

Error: ADADBREGISTER_IND_ADA InstallationDo 2 223

Phase failed.

Error: Main {} 2 223

Installation aborted.

If I knoew what DBMCLI command it had been attempting, that might give me a clue, but as it stands now I have no idea what's wrong, or how to fix it. Can anyone help? I was looking for a more detailed log than what R3Setup provides online, but can't find anything like a WA1.LOG - is there a log file someplace that might geive me more detailed info?

DBMCLI seems to run ok - is there something I can do with that to surmount this problem? Do I need to diddle with registry entries? (I hope not...)

Any and all help will be greatly appreciated - right now I'm stuck!