As far as opencascade is concerned, the situation is the following. nglib/netgen has the following three undefined references
Did you also rebuild nglib(netgen to link against OCCT 7.2? It's correct that the mentioned methods still exist in the new version but all other methods have been removed and also except theASCIIMode
all other member variables disappeared. This means that version 7.1 and 7.2 are not binary compatible and any library using OCCT must be re-rebuilt.
So, this means nglib/netgen must re-built and FreeCAD.