Animations not working/transfering to Mac?

[Rottie_Grrrl]

I've created a PPT, a rather large one (102 MB), and I've included a lot of
animations...it's the same sequence for each slide:

1. Image 1 shrinks
2. Image 1 fades out - with previous
3. Image 2 fades in - with previous

It works great, albeit a bit slowly, on my PC. However when I open the
presentation on my Mac, only about 3/4 of the slides are working
properly...when I view the animation sequence on the Mac it seems to have
deleted animation #1 and changed #3 to "after previous"...but on the other
slides the sequence stayed correct and intact...

Any ideas?