All I can find is this
http://www.agnitum.com/support/kb/article.php?id=1000159&lang=en which is dated 18-01-2011 and it is for 6.0 and 7.0. Though you had mentioned that you used clean.exe already. There is a 32 and 64 bit version of this so make sure you have used the correct one.
You have not mentioned what problems you are having other than outpost has stopped working. Are we just to assume things here? Are you receiving errors?
I would search your registry and computer for both outpost and agnitum. You never know what it might be named. After deleting some of those file/folders that you mentioned ccleaner may help to get rid of any stray registry entries depending on what files were deleted.
You mention that you presently have no firewall. Can you not turn windows firewall on?
If you don't have an image backup I wouldn't recommend beta testing
anything. I would never rely on a restore point as my only backup.
