Hmmmm well..........about the only other thing i can suggest, is borrow/buy a dizzy, and keep it in the boot, 5 mins to change one and can easily be done at the side of the road......keep a 10mm spanner with you and you won't get caught short

Personally i would say with the state of that rotor arm i think it would be fair to say that was your main problem but.....getting a spare dizzy would be a sensible option