In case anyone else has issues installing the v22 firmware the wiki was not clear for me.
I would add another step before "Step 2" can call it "Download firmware". This step would show the commands to download the correct zip file, extract it and put it in the correct directory ready for the following step that references "../USBIRToy.v22.hex". It was not obvious where that file came from. I expected it to be produced by the IRToy-fw_update.tar.gz step. That step only creates the bootloader though.