We are working hard on the new release 1.3.
We always try to keep in mind the simplicity. Now the FileStore is not easy to browse, all emails are in the same folder. We are working on a new Sub-Folder structure that allow users to browse emails by subfolders years, months, etc.
The folders will be nested in any email account folder (yes, we are even working on multi-accounts!). Then they will be organized by a simple path: year/month. And then, inside any folder, you can find the emails of that period.
In short, in your Backup folder (selected in the Preferences), you will have something like this:
So you can browse your emails better than now.