Thanks for the reply,
Yeah if we can boot from the built in flash and have the nodejs / all the other bluetooth packages we require (will they all fit??) that would be fantastic then just use the sd card for our audio files (or can it talk to other external flash I could add to our custom pcb? (need at least 500mb - 1gb for these so internal flash is deffo out of the question.
I don't really want to rewrite my bluetooth scan/connect driver but if its all easy enough should not be a problem.
lets say I have this ported over and I am happy with my .img how easy is it to clone and then flash other devices. If I had say 250 devices to flash can i flash multiple units at once? (at the moment i flash multiple sd cards at once for the pi to speed things up)