Failed to load XnaNative.dll. Please verify that you have the XNA Framework installed.
   bei ImportXnaNativeMethod((fnptr)* method, SByte* methodName)
   bei Microsoft.Xna.Framework.Content.NativeMethods.CreateDecompressionContext()
   bei Microsoft.Xna.Framework.Content.DecompressStream..ctor(Stream baseStream, Int32 compressedTodo, Int32 decompressedTodo)
   bei Microsoft.Xna.Framework.Content.ContentReader.PrepareStream(Stream input, String assetName, Int32& graphicsProfile)