Certainly. In order to adjust your account such that the Auctiva scrolling gallery will be added to the bottom of your future listings, you will first want to mouse over the "Stores" tab within your account and then select the "Customize" option in the "Scrolling Gallery" area.
You will then want to click the "Text & Placement" tab on the ensuing page, check the radio button next to "Below the Description" in the "Placement" section and then click the blue "Save" button at the bottom of the page.
If you wanted to change the placement of the scrolling gallery in active listings to which it has already been added, you would actually have to delete the scrolling gallery HTML from the description HTML of each listing using eBay's "Revise your Item" form. Once you have done so, anyone on our support team would then be able to issue a command on your account that would add the scrolling galleries to those listings again based on your current account preferences.
I hope this helps. If you need any further assistance with this, please feel free to contact our customer support team by mousing over the "Help" tab within your account and selecting the "File Support Case" option.