Here is an update.
The PIC MCU baudrate appears to be 19k2 but the UI config tool software defaults to 115k2, (there is a screen shot in the manual that also has the baudrate set to 115k2), I imagine this is why the PIC won't talk to the BM64 module once you reflash the EEPROM... However I cannot set the baudrate to 19k2 and test becuase today my board appears to have blown up!, I left the power (+15v) connected over the weekend and now the USB port is not recognised when plugged in - this appears to be due to the RESET (RST_N) line been low. The USB/UART interface chip is ok (if you pull this out of reset (manually) then the USB enumerates) but something somewhere isn't very happy.
It appears to be the most odd evaluation board microchip has even produced. The board has the 3W amplifier, yamaha DSP and buttons which can only be used with the PIC but there is no source code to allow you to play with this side of the baord, nor does there appear to be a generally available programming manual for the Yamaha DSP.
The MCU also appears to run at a different baud rate to the BM64 module, so that once programmed only works with the headphone socket and the undocumented (and totally unmentioned) SPKCommandsetTool (UART GUI).
There is no overview of what you can or cannot do with the board, or any manual on how to actually program the moudles (the command set). The UART GUI does log the messages but the order of sending message is left to the user to work out for themselves.
I assume that an "Evalulation" Board isn't a "Development" Board, and the board is only meant to show you that you can connect a smart phone to a BM64 module - (for a couple of hours but not more than 48 !).
At least it appears that microchip is going to replace my board.
I would be interested to hear how others have got on with this board - and whether anyone got the AMP/DSP to work after updating the EEPROM !