Scenario:
Adding new Item column sourced from the Item Sublist on Advanced PDF Template.
Solution:
1. Navigate to Customization > Forms > Advanced PDF/HTML Templates
2. Click Edit/Customize on the Advanced PDF Template to be modified
3. Right Click on the item table to add a new column
4. Input the label of the column
5. For the entries you can use ${item.<internalid>} to get the information
e.g. ${item.custcol19}
6. Click Save