I've bought two and they're great. Excellent quality and very easy to put together. The only problem I've come accross is monitor mounting- but thats just because I used non-standard monitors. They are very fast to answer any questions you have by email, but here's my thoughts:
1. I bought the smaller size CPs (MsPacMan size) and the metal area for controls is 9 1/4" wide, so I would imagine that their 11" panels have 11" wide metal area for controls.
2. I'm sure whatever they do would work fine. Email them.
3. Metal. I don't have the 3rd CP, but I believe it is made of wood and aluminium.
4. Yes, they'll customize anything, just ask.