The change in
ServiceStack.Mvc.SeviceStackController to have public not protected methods in commit 6a4a563de78d06d057ab07d1f9c3555d90469767 causes a runtime error;
Cannot call action method 'TUserSession SessionAs[TUserSession]()' on controller 'BaseController' because the action method is a generic method.
Parameter name: methodInfo
This appears to be because ASP.Net sees the public methods as action methods but these cannot use the generic classes, see MVC App doesn't run with a generic method.
I've reverted these changes and used a recompiled ServiceStack.Mvc.dll and this error is eliminated.
Thanks, reverted them to protected in this commit. This change is available from v5.0.3 that's now available on MyGet.