More LKASSERT , end of check of Multiselect big merge of Sept.12
Pending performance tests on a real PNA with MapWndProc changes
	modified:   Dialogs/dlgTaskWaypoint.cpp
	modified:   Dialogs/dlgWayPointDetails.cpp
	modified:   Dialogs/dlgWayQuick.cpp
	modified:   Draw/Multimaps/RenderAirspaceTerrain.cpp