Thanks Coogan, that's exactly the same page I found and downloaded the drivers from.
After further reading the instructions I found out that they indeed want you to plug the USB in only after the program asks for it. So maybe, maybe if I had removed the faulty USB device, rebooted, started the installer and plugged the pedals in when the cryptic picture with the greyed "Next" button appeared, it might have worked. A new Logitech program numbered similarly to the latest W10 drivers has appeared on my Desktop and it says there's no drivers installed.
What puzzles me the most is that the pedals didn't require any drivers when I last used them!