Data Deploy UDS non root table problem

Foglia

I have Data Deploy set up to do standalone deployments from a DCR such that root level data items go to a parent table and each set of elements of a replicant go to a child table. The parent table has an id for its primary key and the child table has the parent table's id plus a sequence number as its primary key. There are several fields that go to the child table other than id & seq. The problem is that when one or more of the fields is empty, data deploy just skips that row in the child table. Anybody else run into something like this?