Aren't registry entries local?? How would this stop other users on the entire network from running the application if another user is already using the app?
You should be able to set it up in your package and deployment wizard (or other instally program) to not allow sharing of your executables. This should make it where only one user at a time may run the program over the entire network at one time, if I am not mistaken.
Kenneth Gilbert Jr, MCP