ah-ha, I missed that!
I just finished testing for you. Here's what I found.
From their website - TightVNC service is incompatible with Vista/Windows 7/S2008 this will be fixed in the next release, without the service running it works fine in Vista/Windows 7/S2008
I tried to circumvent this, but no luck.
So I looked further and found that the service for UltraVNC works perfectly on my 64bit. Perhaps the easiest and less messiest solution is to use UltraVNC on your Windows 7/2008 boxes. It's totally cross compatible with TightVNC (well they are all VNC protocol

), so there is no need to update your current clients.
Download UltraVNC