While in the Content Manager, the Manage Content button on the Launcher, make use of the columns. To add additional columns, right click long the edge where it says name, and add in the remaining ones that are missing. You can resize them by dragging the divider in between and even rearrange them.
Once this is setup, you can then click on them and sort up and down. Go to the Download Station filter, for example, and then click on Upload Date column. The date will sort various ways, up and down, and you'll see the most recent date at the top. That'll be the most recently available content which can be downloadable.
I do recommend creating custom filters as well such as Out of Date AND NOT Built-in, and so on.
John