Well, I did that and some charts didn't download; so, I rechecked those and made sure they downloaded.
Hmmm... You shouldn't have to re-check them (unless you're talking about tapping on the blue arrow on the right to download them).
A couple days before the flight, I checked it. My err seemed to be I had an internet connection when I checked them.
Another thing that can happen: Not all the charts become available simultaneously - So if you see a bunch of charts available for download, and you hit the Download button, it'll grab everything provided you keep FF open and have a connection the entire time. But, in another day there might be more new charts available and you'll have to download those too. This tends to happen 3-4 days before the rollover date.
Also - When it's finished downloading, the download button will be black and un-tappable, not green. There may occasionally be errors - say your internet connection goes down for a minute or two, the downloads in progress at that point will error out, but FF will keep trying on the next ones so if the connection comes back up, most of them will download, but the ones that error out won't be. If that happens, the download button will be green again, and there will be that badge on the ForeFlight icon on your homescreen and on the Downloads tab within ForeFlight - It'll just be a smaller number.
ForeFlight does NOT do anything like "download all states between here and there." For anyone who may be geographically challenged, a select all might be in order.
Anyway - If you have an active Internet connection and there's no badges and the Downloads button doesn't turn green within a few seconds after getting to the Downloads page, the charts you selected should all be there.
One more clarification worth mentioning: You need to select both chart types, and states you want. Selecting "Missouri" won't get you anything unless you turn on "VFR Charts" for example. There are five types of charts, 50 states plus DC and PR/VI selectable under United States. If you don't select what you need, the badge won't appear and the downloads button won't turn green.
Hope this helps Dave and anyone else who uses ForeFlight!