Okay, made up the USB with Reatogo, but it wouldn’t boot from it. Tried Ubuntu stick - all fine. Went back and ran rufus again and this time didn’t copy over FRST, just to check. Same result - it won’t boot at all - I just get the ‘Reboot and Select proper Boot device or Insert Boot Media in selected Boot device and press a key’

This is definitely a jinxy one …

Got any more ideas? Sorry if I’m a PITA.