ERROR: Custom([file_write,stderr])

[ashea-code]

Hello there, I really want to use this library for a little side project I have going, but I'm running into an issue trying to compile the native targets on Windows 7 64-Bit.
The build_windows.bat worked fined and created the ndll which I copied to the bin folder just to be sure. But I get a strange Error message after it tried to initialize webm.

Error Custom([file_write,stderr])

I'm using the HaxePunk framework as well, here is my code:

import com.haxepunk.Scene;
import flash.display.Sprite;
import webm.WebmPlayer;
import webm.WebmIoFile;

class MainScene extends Scene
{
    public override function begin()
    {
        var s = new Sprite();
        var stringv = "D:/big-buck-bunny_trailer.webm";
        var io = new WebmIoFile(stringv);
        var player = new WebmPlayer(io,s);
    }
}

I can confirm that the file exists on drive D and is not corrupted. Any help is appreciated!

Thanks!