Actually, one of my very first maps was a map of Britannia: http://draconic.ca/portfolio/britannia.png

In this case it's primarily based on the U4-5 map, with bits of U6 and U7. I've been meaning to redo it for ages.

I'm not really familiar with UO, but did they remove the combination runes? ST, EE, EA, NG, and TH are each their own rune in the single player games.