You should be able to download and install WireShark to capture network traffic that is occurring on your machine, so you could look for the UDP transmissions from your machine destined for port 7700.

If you have another machine you could also write a receiver to display the bytes received and change the IP address to send to that machine instead of the panel. You may have to turn your firewall off or add the port to allow the transfer in on the destination machine.

How is "Delay" implemented? Perhaps if it is hanging up the GUI thread, it is also affecting the udpSender.Send method, although I don't know if it would. Is a Delay of 5 suppose to be 5 seconds?