Copy Document Not transferring custom fields for Serialized record

WearAllHats

I upgraded a client to NAV 2015. Most of their Finished Goods inventory is Serialized, so they use item tracking when selling items. There are over 20 custom fields in item tracking (Item Ledger) with very valuable info for each serialized item. When they use the "Copy Document" feature, which they use for returns (quite often), the system does not bring in the values for the custom fields back to the return order / credit memo. In NAV 2016 there is a codeunit 6503, "Item Tracking Doc. Management" that appears to handle this. In NAV 2015, this codeunit does not exist. Has anyone dealt with this in NAV 2015? My client needs to be able to select "Copy Document" and copy a posted sales invoice into a return / credit memo and have the item tracking, table 337, fill in with all the necessary information. I know this is odd, but it's a big problem for my client that I have to resolve. Any help is appreciated.

CodeViper

wait till you find out that in Nav2018, codeunit 10201 "Transfer Custom Fields" is not called in any of the posting routines like it was in prior versions... all that code you have ... has to be migrated back in..."someplace"...