Firstly the install uf2 didn't download, but was in release. I've fixed the boards definition (installBoardName) so that now works.
Secondly, I've got circuitpython installed, so now installing WipperSnapper I see the yellow lights, but no drive appears.
The serial console shows a repeating message:
Fatal Error: Halted execution!
ERROR Initializing Filesystem
I'm assuming initially that I need to format the device first, using the universal nuke from pimoroni, because the official one might not erase all the memory (see raspberrypi/pico-examples#642)
-EDIT- Assumption was wrong, same error after erasing. Looks like our fruit jam firmware is being built with zero bytes for the user file system partition. Updated ci-arduino repo in branches/ci-wippersnapper-fruitjam-fs-size
Test PR in #814