Hi, Linda!  Well, let's see... this is a little harder for me, as I wasn't privy to Anna's contract negotiations, and I didn't return the second season to find out the scuttle butt.  However, what I did hear is that she received an offer for a project in L.A., and she felt that her opportunities were better there.  I liked Anna alot, she was a great gal, was very athletic, and was willing to train and learn things to help her characterization.  From what I've heard, Barbara Griffin (Anna's replacement) was also very good to work with, and she did a great job as well. 

Linda would also like to know: 
"Are you & John Medlen good friends because I see that you both worked on Highlander: Endgame, Beowulf & currently working on the TV series Alias?

If I had one wish, it would be that everyone could get a chance to meet John Medlen!  John is my best friend, and we have worked together on many projects.  He was the stunt coordinator for that first season of Robin Hood, and I was his assistant, and we shared many of the duties that the show required of us.  He was the right man for the job, however, and the vast majority of the entertaining action elements from that first season came directly or indirectly from him.  He is truly a talented man in so many areas.  He's a great actor, Martial Artist, Stuntman, Stunt Coordinator, and Director.  He's also a great family man, and a role model for those who come in contact with him.  Keep an eye on his career, as he will definitely be a huge success in this business!

On my site, I received an email from someone that said Mel Brooks was told by Matthew that he ran away as a young man and joined the circus. Is this where he learned how to do the knife twirl?

I am not 100% sure about the circus story, but I loved Matt's stories of working with Mel.  Mel is a very fun loving man, and Matt worked with him on Robinhood Men In Tights, and Dracula Dead And Loving It.  Matt's stories were almost like listening to hilarious family anecdotes, and I know he loved working with Mel.
 

Second:
Whose idea was the Fantastic Wall Walk? All of us are still blown away by it. 

Let's see... this is how I remember it... Matt and John were designing the Robin/ Francisco fight, and I was there helping them bounce ideas around.  In "Golden Arrow" John did a great fight scene doubling Matt where he performed a "walk up" back flip off of a tree trunk.  Matt loved that move, and wanted to either do it or something similar, and John suggested the "wall walkover" move.  John and I showed it to him, he loved it, but we kept it a secret, since the producers were very nervous about Matt possibly getting hurt doing his own acrobatic moves.  So, on the shoot day, they perform it, and you can see in the shot that they look at each other in an "Oh Yeah!" laughing way after he landed it... and one of the producers about had a heart attack!  In the end, though, it was a great day!

Link to Arabian Knight Battle Photogallery