I am using Artemis and trying to extend EntityProcessingSystem<SpatialForm, Transform>.  However, it is telling me The non-generic type 'Artemis.System.EntityProcessingSystem' cannot be used with type arguments; however, it must be used with type arguments.  Any idea what is going on here?
I am using Artemis - https://github.com/thelinuxlich/artemis_CSharp and StarWarrior as my tutorial - https://github.com/thelinuxlich/starwarrior_CSharp