adp001is correct, the P6 version of the script will only work with textures in the main Runtime.

I'd try the P7 version, as the method that deals with textures got changed to cope with the fact that textures might be elsewhere than the main Runtime.
Alternatively move/copy the textures to your main Runtime and change the relevant nodes to point the the new location (save Material collection, edit paths, then apply and resave PZ3).