When you say "converting them from mt5 to pz2", I assume you mean by using the free utility on ShareCG called "MC6/MT5 to PZ2 Batch Converter"?

Esha has instructions for hand-editing to convert between formats, here, using a text editor... http://www.esha.at/Knowhow/Knowhow_E/Material_E/material_e.html

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