Frequently asked questions - BS.Player wiki http://forum.bsplayer.com/subtitles/...subtitles.html
Further: Is "Use new subtitle parser/renderer" (under [Subtitle properties]) selected or not?
Try if changing that setting does make a difference.
Perhaps verify the actual script used for the subtitles while the movie is running
(rightclick > Subtitles > Primary > Subtitle properties > Font ...)
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adicoto: your search-link doesn't work