Using OpenMV IDE to follow these instructions: https://docs.arduino.cc/tutorials/nano-33-ble/getting-started-omv
It crashed immediately as I click OK for "Install the latest release firmware (v4.1.1)". That's what it says rather than "Reset Firmware to Release Version". The crash is quite reproducible.
MacOS Big Sur 11.6, OpenMV IDE 2.8.1, ARduino IDE 1.8.16.
Had already loaded Nano33_updateBLandSoftDevice which said it flashed correctly but did NOT result in being asked any questions about updating the bootloader or "want to install the softdevice".
Where do I go from here?