Are you sure you hit the keyframe stop watch icon to begin the animation of the properties? Consecutive changes to that property will auto-create a keyframe.
1st to set as "we have this property from prior to this point" the 2nd keyframe will apply itself and be the "I will now be this value, a 3rd keyframe would act as a "kept value to this point" then the 4th is the final value destination.
Sorry if you are sucking eggs here...
JB
Jon Barrie
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