Hi I have gone in a slightly different direction. I have combined the Fluxamasynth board with a Mega2560. The conversion was very easy as I had been previously using a 1980's Roland classic stand alone synth' on a Uno board and all I had to do was change the code to
Serial2.begin(31250);
And connect the center pin of the fluxamasynth jumpers by soldering a half a prototyping cable to that center pin and poking it into Pin 16 socket on the Mega board. The signal was 5V, standard logic compatible, straight through!
It meant I could debug with the standard serial interface and simply direct all midi controls through Serial2 (ie Pin16). I plugged it in, stacked on the Mega, and it worked first time. A rare satisfying feeling 
The Fluxamasynth is ideal for me as I wanted to create a portable device and did not want to lug around keyboards etc. The quality for my purposes is excellent and has a wealth of features and I am not even going to elaborate on, but I believe it can also be driven by SPI techniques as well. Given I have already got a 512k ram expansion and a OLED display on the SPI it was a relief to have the simplest midi interface work so easily.
Rob