GSD can not handle UDP. TCP only.
You will need to write a C++ driver.
To do this, use the device template as usual, delete the launch command "Generic_Serial_Device" .. and use DCEGen (there is a page on the wiki) to create a C++ stubbed device that you can fill in an implementation for.
You will also need to do a checkout of the source code, and set up development packages needed to compile C++ code.
If you wish to pursue this further, come by the #linuxmce-devel channel, and we can help.
I know you probably didn't expect to hear this, but at least it is possible, and not too difficult if you understand the programming.