Hello Dave,
You are awesome. This works. Now i am able to update generic material in Customs document. I just change the logical system group as ERP while creating material in GTS and it worked.
Now i need to update some data in on Classification tab in Customs document item. I found class /SAPSLL/CL_CTSGEN and method MAINTAIN_OBJECT to update this by using GTS BADI /SAPSLL/LCC_DOCUMENT, but not sure this will work at the time of Customs document creation (Class method needs GUID of Customs Tariff Number). Also, this BADI item structure is protected and i am not able to make change in it. I need to change product description that is coming from ECC in additional data. If i am changing the description from ECC it is not getting reflated in cust. doc and taking description from GTS product master data. I need to replace it.
Please suggest if some BADI/Exit available just before creation of custom document.
Thanks,
Sumit