This all looks really cool! MTP is useful indeed, and I'm excited you're adding support. I'll certainly try it out and report back.
For my current project, MTP isn't ideal because it's being used in a lab full of...
I'm designing a project that records audio (WAV files) to the SD card on the audio shield, inside a waterproof enclosure.
I'm hoping to be able to connect to my laptop via USB, and see the files on the SD card as...