Hi TenaC,
There's a .net version, called DarkGDK.NET. It's possible to use it with any .NET Language, including C# (which is the language I use).
Until last year, it was available for anyone to buy, just like DarkGDK (C++), but with the agreement Microsoft and The Game Creators made, it is now free for non-commercial use and paid for commercial use.
DarkGDK.NET is going to be re-released this way on the next couple of weeks maximum (I think so). I'm actually working closely with APEXnow (the person who did the .NET version) to get it released as soon as possible. I'm also working on plugins to extend its functionalities.
What I can say for now is that using the .NET version with C# is... PERFECT! And also, it does come with Full OOP support out-of-the-box so you don't have to mess with all those IDs.
Stay tuned! Ps: Sorry for the long post
Thiago