Adding cart button to Ice theme

I've added cart buttons in various places but I can't figure out how to add the cart button in one last place. The last place I need to add the cart button is below the thumbnails in the galleries for images only (I don't want cart buttons to appear for the gallery thumbnails because I would never want anyone to add every image in a gallery folder to their cart). I've cut and pasted code from various locations in various templates but I can't get it to work.

So, on a page like this:
http://www.dananeibertstock.com/gallery2/main.php?g2_itemId=90
I want there to be cart button below each thumbnail that would let a user quickly add that image to the cart. Anyone know how to do this?

Gallery version (not just "2"): 2.3
Module / Theme name & version: Ice rev16034
PHP version (e.g. 5.1.6): 5.222
PHPInfo Link (see FAQ): http://www.dananeibertstock.com/gallery2/phpinfo.php
Webserver (e.g. Apache 1.3.33): Apache
Database (e.g. MySql 5.0.32): MySql 4.1.11
Activated toolkits (e.g. NetPbm, GD): Dcraw, JpegTran, NetPbm
Operating system (e.g. Linux): Linux
Browser (e.g. Firefox 2.0): Safari 4