Not sure if you figured this out... but this seems to be what you're looking for. I was in a similar situation. My application had a card button that launched a custom form. Purpose of the form was to provide checked listbox items based on the selection of a dropdown (I needed multi-select ability for the items). This functionality is required both on the file card as well as the template card. The methods in the API help for getvar/setvar focused only on datacards with files.... nothing on template cards. The method in the link worked perfectly.