I've got this problem, too. Player opens movie with no problems, but when freezes when opening subtitles. It happens only with some movies&subs, others work just fine.
It might be that:
http://forum.bsplayer.org/viewtopic.php?t=5209, but i'm using so called "TMPlayer format":
00:03:16:Jestem twoim fanem numer jeden!
00:04:05:Więc postanowiłem...