Vendor Credits not on A/P G/L

We are new to NS A/P.  We have been using Peachtree for A/P and importing the transactions to NS.  Now that we are finally making the switch (slowly -- we are only recording transactions directly into NS that we pay electronically), I am having trouble reconciling the A/P G/L.  The vendor credits (a.k.a. Bill Credit) are not showing up on our trade accounts payable when I run a balance sheet and drill down into the G/L account.  When I view or edit the Bill Credit (from "Lists") I can see that the correct A/P account was used.  And, I can