Next step for the #MNT Reform Keyboard 4.0 trackstick mod: The Sprintek SK8707-01-005 works well with a RP2040 flashed with QMK. Thanks to gordon (npub1pnw…4eeq) I found the magic patch which made it work very smoothly. Link to that patch and my full diff to QMK here: https://github.com/josch/qmk_firmware/commit/56d908063fc2641c6257c13ad23b8f072cb37579