How to solve a AddInLoadingException
The common reason for a AddInLoadingException is the fact, that ANX was not able to find a AddIn that is hosting a InputSystem, RenderSystem or SoundSystem. ANX is searching for this AddIns in the same folder where it was loaded from.
If you start a ANX game and you get a AddInLoadingException("couldn't get default input system because there are no registered input systems available") exception this is a suggestion that you have to put a assembly containing a InputSystem in the same folder where the ANX.Framework.dll is located.
You can do that manually (copy file) or by adding this assembly as a reference to your game project (right click on references folder in Visual Studio and select add reference).