The recently published Dragon Quest V TAS has softsubs in the official encodes. They're the author's brief translation of the plot to English and a few other notes.
When I made the encodes, I did that for mkv downloadable (I also can do it for mp4 downloadable) and the youtube. But how is it done for _512kb? I just lazied out and left no subs at all in the _512kb, but that's sloppy, so I'm going back now to fix it... except I can't. I muxed the SRT track into the mp4 using mp4box, and the resulting file plays fine in mpc-hc, with correct subtitles and timings. But trying to play it locally with JWPlayer gave no subtitles, and uploading it as a test item to archive.org gave no subtitles in their player either:
http://www.archive.org/details/CcTest_866
Does anyone know the correct procedure for this?