I have no personal experience with SmartDashboard, but since last year my team uses the UDP on port 1140 (if I recall right?) to communicate with a custom dashboard we make in C#, and if you check out the Team Update on the 24th of January, I believe the port for Dashboard to Robot communications is UDP 1150, you can, without much effort, create a C# dashboard to communicate with the robot using UDP
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I know my answer is not 100% relevant, but if you do not manage to find your answer than I hope this is of help to you. Good luck!!