Thanks for report! We are aware about this problem, but at the moment we are unable to reproduce it on our test sets. Seems like the bug occurs only one PC's with some specific configuration. But anyway, we can confirm that the bug exists and we are trying to fix it. I really hope that we will post a new bug fix build within a few days (hopefully tomorrow).
If any of VNC Manager users experiences the same problem, please post to forum or directly to SmartCode (bugs@s-code.com) information about test steps to reproduce the bug. Because now we are having a hard times reproducing it. And it's very hard to fix the bug, which is ureproducible.