I just grabbed the latest latest version (beta 35), and the "overall" filter does not appear to propagate down.
I set the filter (in Settings, main page) to have a max download age of 7 days. I then go into a group and it shows the max download age of 1 day. And shows no posts. I then change the filter in the group to have a download age of 7 days and posts appear.
Also, a UI thing that's been there a while (iPad2): when I click in the search bar in a group, a dark overlaid "box" appears, probably 2.5"x4" (width, height), under the left side of the search bar. When I cancel the search it disappears.
Groups - the group list isn't collapsable. If I click the "+" next to a group like "Unsorted", I get 2 popup error boxes: "Group Command Incomplete No groups defined to load". Also, since the group is expanded, it should have a "-", not a "+".
Also, a usenet group itself shouldn't have a "-" or "+", it needs some way to denote it is a group, not a folder.
Overall, again, it's pretty handy. Thanks for working on this!