Finished shots not finished.

So I was looking back through my thirty-odd completed shots last night and realized I have a problem. The opening sequence is shot against black- not only because I like the look, but also to make compositing the different elements easier. Or so I thought. I was previously working in AfterEffects on an old Mac with a regular CRT monitor. Everything looked fine on that setup. Now that I have transferred the files over to my new Mac with a nice bright LCD, I'm seeing a lot of problems with my composites. Mainly, all of the mattes and layers I created for combining elements are showing up as mismatched black boxes. The blacks don't match. So where before I saw just an even black background, now there is a patchwork of boxes and junk mattes. You can see what I'm talking about in some of the stills below. I'm no AfterEffects master- so if anybody out there has some suggestions for fixing this problem, please add it to the comments below. THANKS!