Hmmm... that all balck look is tres Goth, eh?
Yup - I've just coughed up for Zicom Mentor (with a name like that how can you resist it?

)
It's actually pretty detailed, and not a top level overview at all. I'm still a bit of a beginner with the UML, and a good portion of it is inpenetrable-ish.
However, it's a matter of context. I'm finding that every day I'm 'getting it' more and more with the UML, so using the Mentor to look up exactly what a symbol is supposed to do is meaning more and more to me.
Personally, I feel that it could do with more by way of a top level overview, as I'm aware that there's a core set of UML symbols that cover 90% of what you need. There's no way to distill this out of the Mentor's barrage of detail.
Have another look at the sample version, as where there is some actual content, it's pretty representative of the rest of it.
All the best
Andrew Webster