How do I use split-screen effect in iMovie 10?

[Sashimi_Sensei]

Specifically: I have two shots A and B. I want Shot B to slide in from the left and be desplayed in split-screen with Shot A. After about 5 seconds, I want Shot B to spread accross and fill the screen, replacing Shot A entirely.

So far, all I can work out is getting B to slide in and appear in split screen. But the effect always ends with Shot B sliding out again and me being left with Shot A.

Is what I'm trying to do possible with iMovie 10 or do I need to upgrade to Final Cut Pro X?

Any help/advice is much appreciated.

 

[MightyGem]

Try here:
https://www.google.co.uk/search?cli...-8&oe=UTF-8&gfe_rd=cr&ei=TjTuVN-AI5KAUIDcgsAN