Hi,
Hmmmm....I understand your confusion.
Templates aren't 100% of what goes into building a listing. In essence, the Template only constitutes the portion of the "eBay defined" section of the listing called the DESCRIPTION section. That's all the HTML code and/or text and pictures and the Auctiva Store Window code. That's why you can copy and paste the Saved Listing code using the <HTML> icon directly to eBay's description section.
The Seller Details profile relates directly to tags used in Templates. That Profile is selected directly right of the box for selecting Template in the one-page lister. Think of the Seller Details as text entry that supports those headers, like Payment. You can also create a Description that's part of an Item Details profile and that is obviously used in the template tags.
The other Profiles support fill-in areas on the one-page for sections, like the Shipping Tools section. Don't confuse the Shipping profile with the Seller Details profile that has a Shipping fill-in (which is text and maybe some HTML to support the text).
You can choose a Template as part of an Item Details Profile. That profile also allows you to choose a Seller Details profile to go with the Template. Maybe that's where you're having the disconnect with getting the Template and all the Seller Details stuff to insert correctly?
Once you've chosen a Template, you're able to use the add Image 1 - 24 on the one-page lister. You can also do that in creating the Item Details profile. Those 1-24 image tags are positioned and type of view method chosen (like thumbnail) using the template selector.
Danno