I believe I know what you are trying to do so I hope this helps you out.
Up at the top of your screen in Auctiva there is a tab for "profiles". You want to go there and create a "seller profile". Basically this will allow you to enter your payment, shipping, terms of sale, contact us and about us sections with the standard details that you would use for each of your auctions. Once you have done this and saved the "seller profile" there is a drop-down menu to the right of where you choose your template in the create new listing screen under the listings tab. You will want to select the seller profile that you have created and saved under the profiles tab and then each of those fields will show-up with the information on your template.
Profiles are great since they allow you to avoid having to re-type all of the same information everytime you create a new listing.
Let me know if you have any other questions and I will do my best to assist you. I hope I helped you with your issue.