Hello!

I have been using PS 17u for about a week or so, and am really, really liking it.... 

What I have: a 1920x1080 project with 9 picture-in-picture "tiles" filling up the screen, each at 640x360 and each on its own timeline track for editing.

What I can get: For 3 of the tiles to pop onto the screen at the beginning (0:00) of the video, 3 more tiles a fraction of a second after that, and then the remaining 3 tiles a fraction of a second after that.

What I can't get:  A strobe "In transition" on each of the individual tiles as they appear.  

What is happening: Any strobe effect that I place on the first (top) picture-in-picture tile affects the entire 1920x1080 screen, not just the individual 640x360 tile.   (And actually even 'blacks out' all of the remaining tracks for the duration of the effect.)

 I guess what I was hoping is that adding a picture-in-picture effect would create a sort of "wrapper" around a clip, and anything else (transitions, etc.) would happen inside that wrapper (and not affect the rest of the 1920x1080 screen).  And that is the way some of the effects are working, such as slow motion speed, pan-and-zoom on still images, color changes, etc.  All of those effects are working just great on individual tiles.

So.... Questions:

1.  Any ideas on how to get that particular effect (strobe "in transition" on individual picture-in-picture tiles)?

 2. Any tips, ideas, comments, cautions or links that more experienced users can share with a new user about this entire concept involving Picture-in-Picture, transitions, etc.? 

THANK YOU !!!