How to (re)order the offerings from within an offering folder in CA Service Catalog 

Windows

Login to the Catalog UI
In Catalog/Offerings, for the folder AND the offerings in that folder, set the following "Display Settings":
Sort By: "custom - use sort number" is mandatory in this situation
Sort Order: "Ascending"
Sort Number: 10 appears first

Example: 
For each offering in a folder, you can set a value for 'sort number'.
For 5 offerings, start with 10 and increase with 10 (to be able to add in  between in the future when needed).
So: 10,20,30,40,50