add customer
NullReference when hidden item
[LayoutViewEditor support for end user modifications]

http://www.expandframework.com/forum/6-bugs/3866-how-to-store-layout-changes-to-model-on-layoutviewlisteditor/5939.html
13.2.7.2
use ExpressionModelEditorControl for calc members
[TwoDimensionListEditor and EditableTabEnabledListEditor By Aris Papadimos]
Ambiguous match found exception

http://www.expandframework.com/forum/6-bugs/3867-ambiguous-match-found-exception.html#5944
http://www.expandframework.com/forum/13-suggestions/3869-stop-deleting-of-application-model/5958.html
add required rule
use the XpandRole Instead
13.2.7.3