I’ve built a simple circuit with the Daisy and the necessary parts. Front and back attached.
The UI is operated with the buttons on the LCD Keypad, which I now read successfully in the code.
The extra single button is a reset-to-bootloader (BOOT_FLASH attached to a pin?) which makes reprogramming a lot easier.
The three extra audio sockets will potentially be used for: SYNC IN (GATE/CLOCK), MIDI and Audio In.
I’ve also left some space for 2-3 pots.
Now only the UI/edit code remains (great fun!), but work starts Monday, so… 
