Hi Italo,
I'm still not sure if this is related to Mill Products only or if it is an S/4 issue. Are other order types available in your system and client?
You may be aware that with S/4 the default client set-up is without take-over of configuration data from client 000. So if pre-configured data is required you may maintain it manually or run a report as stated in note 2272406.
Does this help?
There is no check list for Mill-readyness. The functions are there and just need to be implemented...
Regards,
Alfred