Hi Sweetiepeas,
Yes, it only shows 12 of your listings, it repeats 12 listings, showing the ones ended ing soonist. Auctiva said that in later updates, not sure when ? I think in May of this year, they are going to try and increase that number to 20 listings showing.
But for now its only 12 in the scrolling window on your auction page. The Showcase however shows everything you have up for sale. Buyers can click on a link in your scrolling store, which takes them to a gallery type store, this is where you can do search commands and put in featured auctions.
The scrolling store is great to attract buyers, but it can also confuse buyers into thinking you only have 12 items for sale. So you need to write something in your template to let them know that the scrolling store window is just a SMALL EXAMPLE of items you have listed.
Hope this helps.