Living the dream! I have some hardware work to do on the STM32 (ie. making a whole design on a printed circuit board) before I can do much more with that system. A limiting factor, as well, is the latency minimization on the USB audio interface. It's still manageable to use for a certain number of effects, but I need to make sure that I can do enough audio processing to have a viable product. The backup is Linux, and I will pursue that in the coming weeks, as well.