Romain, DVDSP has an oddity I've never quite figured out. It seems that when you use subtitles, each one remains displayed until replaced by another one. That behavior does not occur in Simulator, but always seems to happen on any other player.
The solution (aka sick workaround) is to place an additional subtitle at the end of each set (meaning after the final subtitle of each slide). Instead of letters, simply enter a space character. That's invisible, yet DVDSP sees it as a new subtitle.
Sadly, that's the only way I have found to make the issue you mention go away.
I'm wide open to more elegant solutions anyone else can suggest.
And for those who've never seen it before... try it out. Place any number of subtitles on your track (one is enough). Then watch to see if it goes away when its supposed to when you're playing the DVD in anything except Simulator. I'd love to learn how you accomplished it.
bob rice
frameworx media