I spoke to Yaman at RBUSA this morning. He was not able to answer my question directly but passed it on to hq in Italy and they responded to say the RB3 files ARE compatible with RB Evo and Race. It's as simple as opening the file and sending to the connected unit. That made my day today!
All of the add on inline fuel controllers work on a percentage basis. PC3, PC5, RBE, RBR etc.
So if ECU commands X-duty cycle, say 50% then you add 10% via the fuel controller, its sends 55% to the injector as a timed signal.
So at the same RPM's you can directly transfer any map to any other. They may need a little fine tuning once transferred, but should be pretty close.
5th gen was RC45 engine fitted with 180 crank +2mm added stroke. They were tuned to max ignition advance. Max I have been able to add up to 6k rpm is 3degrees on high octane fuel.
The 6th gen revs to same as 5th gen rpm, 11,750 red line & 12,200 ignition rev limiter cut off.
6th gen has narrower included valve angle so valve pockets are cut at a different angle. Otherwise AFAIK pistons are the same.