I just added a MIDI Boutique mkcv64smfu encoder to my console for velocity sensing on my 4th manual. This lets me enjoy piano and bells, especially for three manual sample sets. In the process I did a layout to adapt recent Rodgers (Roland) keyboards to the Fatar pinout of the encoder. The gerber files or a set of Eagle files are available for the adapter. The board is also shared at OSH Park if you like purple PCBs. Get in touch if you want to do a similar keyboard connection.
The encoder is a simple USB connection so no extra MIDI port was needed. The board works as expected after I fixed a primary/secondary contact reversal on my adapter. I think I misinterpreted the Fatar designations of MKx and BRx as indicating make-break when they obviously meant something else.