I have not received a response fromyou about Breakbulk functionality. This is standard WMS functionality in NAV and I think, this can sole your problem.
NAV help quote:
Allow Breakbulk Field on The Location Table
A check mark in this field indicates that the program will meet the order with items stored in other units of measure, if it cannot find an item stored in the unit of measure that is requested on an outbound order.
The program first breaks a larger unit of measure of the item into smaller units of measure to meet the order. Here you are breaking the bulk unit of measure that the item is stored in.
If a pick line still needs items, the program suggests that you gather items in smaller units of measure to meet the order. Here you are breaking the bulk unit of measure on the sales, transfer or production order. For example, when the order requests a pallet, and the warehouse has only pieces, the program creates a pick for the number of pieces that correspond to a pallet.
This field can only be used when the location is set up to use directed put-away and pick.
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