hi stuart.rauch,
Thank you for your post.
The reason why your template is automatically used when creating a new workbook (excel file) is that you use the excel application interface to do this for you. However when the data is exported by 3rd party applications (such as TDP) then certain app-interface features are ignored. Right now there isn't any setting or feature that will take your template while exporting.
The workaround might be for you to add an additional step before the export step to simply copy the template from the folder you've mentioned in the export step's input path and disable "overwrite file" with append data on the export step - in this case the formatting will be kept.
Martin