NullReferenceException when creating instance of Game class (OpenTKGameWindow.Initialize)

NullReferenceException when creating instance of Game class
(OpenTKGameWindow.Initialize)

I just installed xamarin and monogame on OSX I have tried to run a really
basic demo project that works perfectly on windows. But I get the
following error:

System.NullReferenceException: Object reference not set to an instance of
an object
at Microsoft.Xna.Framework.OpenTKGameWindow.Initialize () [0x00000] in
<filename unknown>:0
at Microsoft.Xna.Framework.OpenTKGameWindow..ctor () [0x00000] in
<filename unknown>:0
at Microsoft.Xna.Framework.OpenTKGamePlatform..ctor
(Microsoft.Xna.Framework.Game game) [0x00000] in <filename unknown>:0
at Microsoft.Xna.Framework.GamePlatform.Create
(Microsoft.Xna.Framework.Game game) [0x00000] in <filename unknown>:0
at Microsoft.Xna.Framework.Game..ctor () [0x00000] in <filename unknown>:0
at test.Game1..ctor () [0x00057] in
/Users/remojansen/Desktop/test/test/Game1.cs:37
at test.Program.Main () [0x00001] in
/Users/remojansen/Desktop/test/test/Program.cs:19
There is nothing wrong about the code so I must be missing a DLL or
something? Do you have any ideas about what could be missing?
Thanks :)