Well
i will tell you;
1.Record movie from your replay
2.play it on quicktime player or any other
3.in the moment you want to make gif push pause and after that printscreen.This would be your 1st frame.Open Photoshop and make a new document.Push Ctrl+v and after that push alt+tab to get back to your movie.Push the right buton arrow to rewind the next frame.After next frame push again printscreen and past it on your previous frame in PS.After you finish with Frames you can Crop your frames.Get crop tool and select the part you want to see in the gif.Push Ctrl+enter and it will be croped.After that you can choose size from Images->Image Size.After finishing this you need to save your file in psd and open it in ImageReady.
4.After u open your psd in Image Ready you have to put the arrow in the down centre of the screen and select ''Make Frames from layers''The frames must be created.After that you need to remove the 1st screen if it is white only
Then go to File->Save Optimized As
and Select Gif and the Gif will be made
GreetZ! Sorry for the long post!