Why will quicktime 7 not play mp4 from windows

So I made a video with an H.264/mp4 format using a program called Lightwave on Windows 7. When I transferred this file to quicktime 7 on a mac for a presentation, the first image looked fine for about 3 seconds, then the colors were all changed around and faded. However, when I went back to quicktime on windows 7, it works just fine. Does anyone have any suggestions?