I know I said I was going to wait for Version 11 but decided to play around with ZA Free 10.1.101.000. I thought I'd pass along that my Firefox issue discussed in this closed thread:
appears to have been resolved. I had Firefox 11.0 installed and waited until Firefox 12.0 came out and downloaded ZA Free 10.1.101.000. I updated FF, restarted Windows a few times and, each time, tested opening FF. FF no longer became locked in memory.
So, if anyone else had this problem before, I'm passing along that I came across a solution.