First, the biggest help I have found in using VNC is enabling the BeOS pointer to follow the VNC pointer on the server machine. In my case this was not a default option yet could be a bug in my system. However for the record, to enable the pointer to follow the VNC server pointer simply open a folder within BeOS then move the pointer unto the VNC window. You should then see the Pointer sync'ing with the VNC pointer which is extremely helpful in using this fine piece of software

Second and last, for those who run VNC a lot like I do you have probably notice its slow, especially slow if the VNC sever machine is on a slow network and/or the VNC server is not optimized. This is usually taken care of using a updated version of the VNC server with a high performance network OS. To do this would mean running the VNC server on a linux/windows/Mac machine or whatever the VNC server runs on. This will extremely increase the speed of the BeOS VNC client. In my case I use a home network with a a NT machine running the VNC server and use my BeOS machine to connect to it for whatever reasons.