Hi Paralee,
In my experience, assets in Marketo are sorted by alpabetical order in all cases within a particular folder or Program. I work for a Marketo Services Partner, so have access to multiple Marketo accounts, and all have alphabetical sorting.
When cloning a Program, its assets are initially sorted by the order they were created, but if you leave that tab and come back, or logout of Marketo then log back in, they will be sorted alphabetically.
If you're seeing something else, after switching tabs or loggin out, take a screenshot of the sorting you are seeing and post here.
Thanks!