D, DLLs, UnrealScript and UDK (Sort of a complex question)

[Trass3r]

> So, my question is THIS:
>
> Can I write a "windows" DLL file in D that would have functions that can  
> be accessible from a compiled C++ program?  (Actually, in this case, it's
> UnrealScript that is compiled into a C++ exe.)

It's perfectly possible to create DLLs with D, also see
http://www.d-programming-language.org/dll.html

I already successfully used a D dll with C interface to create Matlab  
plugins as well as a D dll exposing a COM interface to hook DirectDraw.