I'm running XP Pro SP3 with the NET.Framework (all) additions.
Installed CCC/driver as best I could (error messages and all).
Then, I copied cli.implementaion.dll and mom.implentation.dll to C:\, to the folder the CCC/driver (downloaded) was in, and to C:\Windows\System32.
Un-installed CCC with ATI's install manager thru Add/Remove Programs.
Ran the downloaded install/setup again.
CCC and driver now work perfectly.