Sel.=Sel.-"A"/"C"=A-B
LMB:Remove -Selection in "A" from current Selection.**_
RMB:Remove Selection in "B" from "A" put in "C".
Restore_UnSelect(GA)
#END
[OnRightMouseButton!]
GX=Remember_Selected()
Restore_Selected(GA)
Restore_UnSelect(GB)
GC=Remember_Selected()
Restore_Selected(GX)
#END
