We have a customer using Landed costs during RoG, set to go to a specific GL account, which is matched up with the eventual AP invoice.  The problem is that different items have different duty rates (some lines with zero added costs).  We set things up to use Weight (with ShipWeight set to zero for items with no duty rate), and a script to calculate the total DUTY amount, but Sage allocates proportional amounts to lines by an algorithm that differs from the line-by-line logic of the script, so the final unit costs are sometimes incorrect (when there are lines with different duty rates on the same receipt).

I've looked at a couple Landed Cost enhancements, but neither gives line by line control on the landed cost amount.

What I'd like to do is set the AllocatedLandedCostAmt in the detail table (overriding how Sage distributes the line amounts), but the field is marked as Read Only.  (This makes sense because the total of these amounts must match what is in the PO_LandedCostReceipt, which might involve multiple cost types, so the GL amounts match the increased item costs being posted to inventory).

Does anyone have any ideas of how to deal with this problem?