The default movie is called "Slideshow" DO NOT delete this.
Make a copy of this movie track and edit it. You might make multiple copies of this movie track and edit them down to suit your requirements.
You can make as many movie tracks as you like. But you will need to set one as the new default.
Each scene can have it's own movie track or each level or each entry (whatever you like). You just assign a button or hotspot to your desired movie track.
Movie tracks can have different rotation direction or speed, limited rotation, zoom in or out etc. Customise as you like.