I'm getting an error when in the Security Editor. 

If you choose the top level Permissions and then select any permission from the right pane "All Permissions" view.  You get the error displayed below, I also got the same error running form the RBS Sample.

Exception
  Could not create permission editor.

Source     : MicroFour StrataFrame Security

Stack Trace:
   at MicroFour.StrataFrame.Security.SecurityDialog.CreatePermissionForm(Int32 ProjectPK, Int32 ItemPK, String Category, Boolean IsCopy)
   at MicroFour.StrataFrame.Security.SecurityDialog.EditPermission()
   at MicroFour.StrataFrame.Security.SecurityDialog.lvDetail_DoubleClick(Object sender, EventArgs e)
   at System.Windows.Forms.Control.OnDoubleClick(EventArgs e)
   at System.Windows.Forms.ListView.WndProc(Message& m)
   at System.Windows.Forms.Control.ControlNativewindow.OnMessage(Message& m)
   at System.Windows.Forms.Control.ControlNativewindow.WndProc(Message& m)
   at System.Windows.Forms.Nativewindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)

Hi Purnell.

You are probably trying to edit a permission at runtime, is that so?

If this is the case, permissions are not supposed to be edited at runtime, only at design time. This exception will probably be treated differently in the future.

Cheers.

Ivan is correct.  There are some options to prevent certain things from showing at run-time, but if you could provide more details as to how you generated this error it would be helpful.  Thanks.