I have an item that has order type "Manual" and I'd like to change it to "MRP". Baan does not allow me to change without removing purchase orders, inventory, etc. It's very tedious to do all these. I am thinking about just changing through GTM and let MRP take care of the rest. Any comments on this?
TIA.

We're on 4c4 and do this quite frequently in GTM without any adverse impact.
Regards
Gary

Yes you can change through GTM the item parameters and when new items is planned then system will automatically take cares with the new parameter.