FLV not playing within two SWF files

Question

Before I start off; I'm not a pro at Flash at all.

Folder structure:

• start.swf
• assets/moviecontainer.swf
• assets/flv/movie.flv

What I want is to open start.swf, have it embed moviecontainer.swf which has a FLV playback object that loads in the movie.flv.

When I check my moviecontainer.swf, it runs properly. But when I use start.swf it loads moviecontainer.swf (because I can see it has the background and all) but the movie won't play (and I think the buttons don't work anymore)

I have saved both .swfs with the "Local files only" option. I have no idea what the problem can be, as I said, I'm no Flash pro and I have no experience as to say "oh it looks like we got that xyz problem.."