Hi Rafke!
I think TMPlayer's subtitles don't have an End time.
In this case BSplayer assumes as max subtitle duration the value setted in Subtitles section in Preferences window.
The problem is that with a plugin you have to tell BSplayer the Start time, and
also the End time...
What does appen when you put 0 as End time, or the same time for both Start and End??
For a description of the different subtitles format I think you have to search the web for every single subtitle format (unless someone will post here a link to all the tags), I used SubRip to convert .srt format to MicroDVD format to know which is the italic tag for it (
{y:i}), since I knew that SubRip has as italic tag.