I've taken a look at the subtitle feature in VideoPad, and as far as I can see this feature is not suitable for embedding optional subtitles in a .mp4 file. By that I mean the kind of subtitles that each individual user can select or de-select via the video player. Is that correct?
If so, it would be great if you added this possibility to a future version of VideoPad. I need this facility, so I'm going to have to evaluate and learn to use a couple of other programs to create the subtitles and to embed them in the .mp4 file. It would be much nicer to be able to do it all in VideoPad.