Transcode the footage to a prouction codec using any app that will open the video and alow you to do so. I don't know if Magic Bullet Grinder supports that kind of footage but there has to be something that does.
Come to think of it, I think the files work just fine on a Mac.. What's your OS? Have you tried?
Have you actually tried importing this footage into After Effects?
I have tried several different ways with a Canon XF300 and what happens is you can do a RAM preview and it will play just fine, but if you try to scrub anything past it or just play it will crash instantly.
There is an ongoing discussion on this topic.