Sharing the same option for the accessibility render mode and for the view mode is not a good idea, really.

So, create a new ViewMode setting for the single/facing/columns view mode (leaving the RenderMode for compatibility with KPDF).

Rename [Rr]enderMode into [Vv]iewMode in the page view, following the new name of the setting.

Remove the "padding" enums from the settings, as it seems they have no real use beside giving issues.