I have submitted my assignment on Oct 17 and took part III on 21st. Guess I didn't have to wait long compared to some who had to wait 6+ weeks.
Clearing the certification makes me feel good. I am not sure how much it is going to contribute to my career but the process definitely made me more knowledgable and forced me to learn topics which I woundn't have done otherwise.
My assignmnet had 11 sequence diagrams primarily for each use case described and alternate flows. I also used 2 seperate sequence diagrams to illustare Web and Swing app UI interactions. I did not provide sequence diagrams for use cases without specification.
I guess the diagram I had most trouble with was the component diagram. There was no easy way to come up with a single diagram without loosing simplicity.
The approach I took finally was to draw component diagrams with varying levels of detail. ie. one to show major components of the entire system without getting into details, one to provide more detail on EJB tier, another one focusing on UI components etc. I have also included a deployment diagram. Having a deployment diagram definitely helps to explain the design easier.
My advise to those who are preparing is this.
Keep it simple, make educated assumptions and document all assumptions. Lack of adequate information and disconnections are annoying but believe those are intentional. It is easy to get trapped in details, but shouldn't. A good architect knows where to stop.
Hope this helps.