I have a macro that is using the function written at the bottom. Generally it is supposed to pack and go a model and replace any instances of "XX" and "#" in the assembly/part names with a provided replacement text AND put a prefix on the assembly for example pack and going ZG_XX-#.sldasm to another folder (replacing XX with FG and # with 1) it runs 5 times and changes # from 1 to 5 each time (prefix-ZG_FG-1.sldasm).