Hii Eva,
If the Product is going to be in house production, It must have BOM, Routing and PV in ECC side. You must CIF them to APO as well. We CIF them as PPM/PDS from ECC to APO. Which generally acts as a source of supply and used for Production planning.
If you want to run PPDS/CTM you want to activate PPM?PDS IM in ECC, and have to send the BOM,PV of this SKU to APO. Then only the planned orders generated from CTM can pick the right source of supply, and also can CIF to ECC as well
Regards
Debashis