Hi Max (just guessing!),
you asked: "1. Is it user friendly for the BPMN modeling? In others words, does it require the user to be very skilled, or it is as simple as Visio to use"
Its as simple as Visio. I actually find it much easier to use than Visio. Visio is basically just a drawing tool. Does a good job of that. EA (and similar modelling tools), allow you to draw the diagrams and click through from one diagram to the next if you have multiple levels. It is object based, so you can reuse activities, actors, etc but only define them once. Plus its a multi user modelling tool that exports to Word, etc. AND its about a quarter of the price of Visio.
I've never been trained on EA but have been able to pick it up easily to a moderate level.
you asked: "2. Is it possible to document each step of the process directly in the tool, without having to maintain a seperate Word document? If so, does it have an export feature to generate a Word document with the description of each process steps?"
the short answer is Yes to all of your question. You can export to word. There are some predefined templates to use and you can create your own. Yes, you can define the activities directly on the diagram - cllick on the activity opens a window to enter the details. Then you can use a template to print the diagram and all the activity descriptions. Also the pools and lane descriptions, diagram descriptions, etc if you want.
Thing is its very flexible. I've found that if you want to do something, there is generally a way you can do it. For more advanced stuff you need a toolsmith though.
They let you download a copy for 30 days. Have a play. You should be able to do your diagrams pretty easily. There is good Help and white papers on their website as well. There is probably one on BPMN.
Kimbo