Sousuke, you've resolved your problem
here
But for others, I would add:
If you're interested in subtitles, even Chinese or Arabic... You should
install vobsub v2.18, together with BSPlayer. The filter Dvobsub.ax needs routines from vobsub.dll to be registered.
Once loaded by BSPlayer (a green arrow appears in the tray bar), you may have to edit DVobsub filter settings to feet your needs.
DVobsub now comes with a great debug feature in it's "Misc" tab, that lets you show OSD statistics in real time. It can even help to troubleshoot BSPlayer...
As DVobsub works too with your windows media player (file:\\c:\Program Files\Windows Media Player\MPLAYER2.EXE), you should try it to make shure that your subtitles problems are not related to BSPlayer.