Just happen to read this thread. I can confirm that the setup with the Advansea TR-200 is working!
We are sailing for over two years with the TR-200 AND having occasionaly problems with the master GPS (Garmin GPS-152). We also put a GPS stick outside. We were thinking that its sad we were not able to send ownship to OpenCPN. So not aware of the -already existing option- "AIS Port (Shared)" in the GPS-tab of the settings.
Thanks for the hint!
A verry happy OpenCPN user doing real enviromental testing for the last two years onboard Bodyguard.