Quote: "1) Normal Maps - ZBrush 3.1 will they work in game?"
As long as you export it as a normal map...and dont use the high polygon model.
Why should there be any problem?
(not that they look good, you should wait for Bond1's new gore pack along with his custom shader for normal maps which looks great!)
Quote: "2) What is the max TextureMap Size? 512, 1024?"
You can go from 256x256 to 4096x4096. (i tried it out once)
Not that you want to use 4096, cause thats to huge in filesize and can mess up the framerates.
You can easily create 1024 textures with enough detail.
Quote: "(can you have large winged Dragon) "
Yes you can but! FPSC sometimes gives issues when huge characters are placed.
They sometimes get stuck etc etc.