I've got a demo CD sitting on my desk right now waiting for me to take a look at it again. I used their software about 5 years ago for manufacturing process simulation. It's very powerful, but at the time it had a pretty steep learning curve. I'm sure it's much better now.
We've used Process 2003 (and its predecessors) from iGrafx/Corel for a number of years, and found it easy to use - easy enough that our clients can pick it up without extensive training. (We don't sell the software, just use it). You can link all the maps, link in documentation, and also compile the whole system to the web, giving you a useful access/distribution capabilitiy. The software also has simulation capabilities.