To debug a CHUI client (say, on Linux), first run proDebugConfig <PID> to make the client process ready for debugging and get a port number to attach to. If you don't specify a PID you get a list of running processes to choose from. You may have to be root to run that; can't remember offhand.
Then in the debugger go to the debug menu and attach to remote process and specify the host name and port number.