When you have a Proposal that you would like to export into a a particular Template or Style, you can choose which to Default to.
First you will need to choose the Account in which you prefer to the Template and Style to be:
To choose a Default Proposal Template for Exports go into your Account page and select Proposal Templates:
For choosing a Default Style for exports:
After you have selected your Defaults all of your Proposal Template and Styles will show and default to those designations when you are on the Export page, see below: