But I
*DO* have news on this!
All of the flash chip's pins are available on the header in the top left. So my thinking was to remove the flash from the board, put it on a small piece of perfboard with a header that plugs into the programming header.
Yesterday I did a 'brain transplant' (or, better said: a 'memory transplant') by desoldering the flash of a C9, putting it on a SOP->DIP adapterboard (I'm a through-hole guy) and making a makeshift adapter that plugs in the header. See photos below.
Well, this works

- Next step is to do the same to a different pedal and check if this adapter works in that pedal. So today I removed the Synth9 flash, put it on a SOP->DIP adapter and plugged it into the C9. Whaddayathink: the C9 now is a Synth9 pedal! The reverse also works: placing the DIP into the perf into the Synth9 board makes it a C9 pedal

So now the next step is to put both DIPs on a perfboard with a /CS selector switch. I'll keep you guys posted.
Just some more random thoughts: there might be a connection from the header to the /RESET of the BlackFin. We could use that to reset the DSP and load the new programs after switching /CS. I'll have to probe those connections.
Also, I opened up a MEL9. This one has a different chip, the MX25L12833F. This is a 16Mbyte flash, much bigger than the 1Mbyte flash of the C9/Synth9. It's probably holding all the wavetables. We'll see if that one is compatible later on.

