It should work with the CD based RNS-D but they don't support any language but German right now. The are not ready to support the RNS-E and there is also still the issue with the US RNS-E and unconfirmed video input as well as the speed signal over CAN which has to be filtered out to display the video fromthe 3pmdev. Besides that it's a very interesting project.
See also http://www.navplus.us/forum/viewtopic.php?t=509
See also http://www.navplus.us/forum/viewtopic.php?t=509