You are not "adding" the MD state pickup. The add is on the W-2. The subtract is on the 1099-R. As long as there is an amount and not an EP, then you put the letter P in the State Use Code box and the amount in Box 19-1 Local Distribution. Verify on the MD return from the subtraction worksheet and if a carryover for unused amounts, verify that too on the same 502SU.
