I recently tried to import a .STEP file with the old template with 6061 material. However, I want to mass remove this material so I opened the old part template, removed 6061 from the materials section, saved it, and overwrote the old one. When I re-imported the .STEP file it would not generate any parts and would open a blank assembly. I know it had to do with the template modifying because it would work again if I revert it back to the old one. I don't know why it isn't opening anymore.