Enhancement in Planned order creation MD11

I have a request to add new fields to the planned order creation transaction MD11. Can someone provide tips on how to do this ?

Also some advice on the use of enhancements below would be helpful.

LMDR2001 User exits restr. profiles of opt. pur.ord.-based load bldg

LMDZU001 User exits in additional planning

These are the only ones available for MD11.