Thank you for your help. I use GX420d, it’s a shared, local printer.
What/how is the SVG image being generated from?
Do not generate anything in frappe side if you are using zebra. Let them do all the work and they are better at it.
Your code needs to be carefully designed to be flexible.
@MikeS
I take it you used the Barcode data type for the custom_barcode field? Delete the field and recreate it as a a new field, select Data as the field type. Enter the barcode of B-1-6-001 in the field, you ill not get a preview of the barcode though.
That should get things working 