As soon as I append it it’s automatically converted to a polymesh and I lose the option to change its initialization.
You know, I don’t think you can any more. It might be in the settings somewhere, but if it is, I don’t know where.
I don’t think you can. However if you need to initialize to match your other subtools you can append them to your primitive and then make the changes in initialize and then append it.
Maybe if you explain the context, we could help you find a way around… 