I have since fixed it, but thought you deserved the feedback. I am a longtime ZA user. I got an update message and accepted the default install (v 768) without the toolbar or other options. It seemed to take a long time to allow programs to run and there was generally unhappiness. I saw 780 was available downloaded and installed that, this time custom install, with no options. (Just free firewall, no AV). I use Max security and didn't want the auto accepts or the microsoft list. This also ran slow and prevented windows shutdown. The logging off message would just sit there forever.
I removed ZA and reinstalled, same thing.

I ran clean.exe and that hung as well. Twice.
I removed ZA and ran clean.exe. Then reinstalled. (The latest install is offensive as it seems to imply that you have to accept the toolbar to get agreement.)

However, I think I am finally running ok, programs are still very slow to come up. I understand that it takes a while for ZA to populate its database. Still it seems like it could recognize new programs and prompt more quickly.
It would be nice if ZA would detect and report problems when it can't process its database properly or whatever was causing the hang.
Love the product although hangs, poor performance, and a greedy install is making me question continuing with ZA. I hope the feedback is useful.