As a screen reader user, I'd like to point out some accessibility issues. They are by no means critical, but some of them do somewhat hurt MiXplorer's usability.
1. In all settings-related views the checkboxes report their state only when checking/unchecking them, not when navigating between them. This makes it impossible to find out their state without checking/unchecking them first.
2. The currently selected tab doesn't report its selected state, unlike the state of selected files/folders, which is reported properly.
Also, there are some unlabeled buttons here and there, esp in the media player and the text editor, but they at least have helpful internal identifiers, although it'd be better to have them labeled correctly.