Hmm I just noticed something I thought was strange, I have a base class in Edneeis.Utilities.dll and I use this base class in Tracker.Framework.dll which is used in ObjectTester.dll. ObjectTester only has a reference to Tracker.Framework.dll and this gives me an error when any base class methods are called that originate in Edneeis.Utilities.dll because it isn't directly referenced in ObjectTester. Has that confusing enough? Is this correct does a project have to reference all base classes/dependent classes of the objects it uses? Or did I miss something?

As a recap in my ObjectTester app I use a Nurse object (from Tracker.Framework.dll) which inherits from the DataLayer object (from Edneeis.Utilities.dll). ObjectTester has a reference to Tracker.Framework but not Edneeis.Utilities and this gives an error.