Looking for information on a very obscure gaming book

Hi everyone
I'm hoping someone can help me. I'm trying to find out some information about a very old and definitely out of print book from my misspend youth.
It was called the Rocky Horror Monster Show, had a big green monster face on the cover and was a beginners guide to running your own adventure games or RPGs.
I Remember that one of the mechanics was a table of absolutely anything that listed the difficulty of completing a task from trivially easy to impossible with numbers beside each level of difficulty.
You had to roll 6 D6 and add the number beside the difficulty, if your total was 36 or more than you managed to do your task properly.

There were also plenty of weird monsters listed including the Pondawoozle bird that came as a pair. I think the male was harmless and let you kill it but the female could lay explosive eggs on you in revenge for killing its mate.

Unfortunately I can't find this book online anywhere and my missus thinks I've made the whole thing up. Can anyone else remember this book or was I the only one who has ever heard of this book?