In Products & Settings -> [Orderpage] -> Product:
Clicking on "Update template list from Proxmox" does not load newly added ISO files / templates from Proxmox local storage
1. Make sure that template storage is on one of nodes selected under Resources in product configuration tab
2. Make sure that your ISO files have their content set to "iso" in proxmox
http://pve.proxmox.com/wiki/Storage_Model#Storage_type_Content