But back to the question at hand. It's not in front of me so this is from memory.

There are basically two routes to slo (or fast) motion in AE. both I think are more than adequately covered in the online help. There is Time Stretching whcih you've found and then there is "Time Remapping". Search for that in the online help. Once you've got the right help page I personally foudn that it is more than adequate in shoing you how to keyframes the gradual time changes.

It takes a lot of time and patience to get it just right because you have to allow for the time displacement when placing your keyframes. It's a little hit and miss from memory but it's worth it.

Also, I this function is adequate in AE but not a patch on what you can do with a plugin like Twixtor (Marc is right to mention it). However, I also believe that this area has had a significant make-over for v7.

hope this helps.

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