One issue to consider is if your user can jump forward in the flv.
If they do the cue points are missed and your swf will not update until the next cuepoint.
I used if statements like[php]
if((_ds.time >= 136.004) && (_ds.time < 167.267)){
do this stuff
}
if(_ds.time >= 167.267){
do this other stuff
}[\php]

that way the appropriate event triggered even if the user jumped forward past a cue point. See it here where I use it to scale the video mask and reposition the video. The scaling happens as soon as you land anywhere within the right timezone in the flv.
http://www.orangefilmworks.com/

Of course it the user can not jump around in the flv then cue point swill work fine