Uninstall Version Cue CS2 before upgrading to Leopard?
From a sample size of one, it may appear that the Adobe-supplied uninstaller does not uninstall Version Cue CS2 properly. Well, it never finishes, it just hangs.
I’m not sure where it is getting stuck. Perhaps a manual removal would be a better option. Now to find the list of the folders it uses. I tried using fseventer to see what files were being touched recently but it seems to have stopped working on 10.5.5.

Adobe’s guide to uninstalling
http://kb.adobe.com/selfservice/viewContent.do?externalId=331301
from pureownage.eu :
To remove Version Cue manually (Mac OS only, not recommended)If you’ve accidentally removed parts of the Version Cue installation manually or if the uninstaller fails, you have to remove the remaining installed Version Cue components manually.
1 — From the Library/PreferencePanes folder, drag the Version Cue CS2.prefPane folder to the trash.
2 — From the Library/Preferences folder, drag the com.adobe.versioncueCS2.plist file to the trash.
3 — From the Library/StartupItems folder, drag the AdobeVersionCueCS2 folder to the trash.
4 — From the Applications folder, drag the Adobe Version Cue CS2 folder to the trash.
5 — From [user home]/Library/Preferences/Adobe, drag the Workflow folder to the trash.6 — (Optional) From the [user home]/Documents folder, drag the Version Cue folder to the trash.