I have used my licensed UBB ver 6.04d for more than 3 years without any serious trouble.
I DID move it to diff. servers several times. Including moves from Unix to Unix and from Unix to W2K. This time I have made a move from W2K to Unix(Linux).

http://www.ukrpravo.com/cgi-bin/ultimatebb.cgi

Sure, I followed move manual

https://www.ubbcentral.com/support/docs/ubbclassic/UBB6_backup_transfer.html

Sure I did set all permissions by chmod to proper values.

And the tests shows that EVERYTHING IS SET Okey.

http://www.ukrpravo.com/cgi-bin/ubbclassic_test.cgi

http://www.ukrpravo.com/cgi-bin/ubb6_test.cgi

The problem :
I can NOT access to Control Panel as Admin!

http://www.ukrpravo.com/cgi-bin/cp.cgi

The error is :
No member profile found for member number: 00000001

No Bug in the code in ubb_lib.cgi code file.
It seems the UBB does not have access to the profile(s). But profiles at /Members dir are Ok. I did check them several times.

Try to login as "Nick" - the same result.

For 3 years everything was so Ok, that I forgot my License number and I can not ask for a ticket.
Sure my license is paid.