Not a fan of GPL/LGPL v3/v2.1? Fair enough haha.
My second choice would be the Vala language. It's meant to be similar to CSharp, but it's compiled down to C and then to machine code.
I haven't tried using Vala on Windows though and if I recall correctly there's not much support outside of Linux since it's a relatively new language
so that's probably not a viable option.
FMOD is great though.
Couldn't find anything on Zelgasm though (I found weird comments from around the internet though... >_>). Is the syntax more similar to C or BASIC?
Nevermind. I'm going to assume that this would be a new scripting language created specifically for ZC. e_e
Angelscript looks pretty nice. It gets my vote haha.