Yes, unfortunately the Gadgeteer platform is not further supported by Microsoft in porting it to the latest Versions of Visual Studio (the last is VS 2013). GHI Electronics, the biggest manufacturer of Gadgeteer boards, announced that they won’t produce Gadgeteer Boards any longer. However GHI has announced that they will continue to produce NETMF Boards and that they have started to work on their own NETMF fork. For more information see this blog:
https://paolopatierno.wordpress.com/tag/netmf/ I made a NETMF adaption of your RFM69 driver for the in future available NETMF Boards as well as one for the not longer supported Gadgeteer Boards. I still think, that NETMF Boards could have their place besides Arduino, mbed, Raspberry Pi, Beagle Bone and… and. (not in large scale-production, but for series of perhaps 1 to 100) The ease of programming in C# with VS Debugging for me is not comparable to programming with the Arduino IDE (but I’m only a hobbyist).