Ok, last update. I tried same code on 2.0b8. Then the movieEvent() method proves to be necessary. Adding that back (done in the code above) things works flawlessly and I was able to ad up to more than 10 movies. With no crash or hang.
Also the callback method movieEvent() don't seem to need to be called in each movie, just a plain
void movieEvent(Movie m){
m.read();
}
seems to be enough for all the movies...
edit, just posted that question :)