Why not use Skype?
If you wan to video chat with PC, the best way, I think, is to use Skype.
Skype 2.0 beta works quite well with PC Skype 2.5 (or 2.6 beta, I didn't try it).
Try to reinstall
This happened on me too in beta 6 and rc1. But after I reinstalled the tool and reset the sharefolder, it worked fine. In RC2 it also works. So try to redo these and you may solve this problem.
My computer is macbook pro 1.83GHz with 1.5G memory and guest is windows xp sp2. I just upgrade PW to Parallels Desktop
RC. By the way I also reinstalled the tools. Here is the problem:
At first, when I opened the PSF on the desktop, it just quited the explorer without any report. Tried...
It may be caused by VPN.
I had the same problem. Even win xp had an IP address, router and gateway address, I couldn't ping between the host and guest systems. But when I quited the VPN(CISCO), the connection was back.