I don't believe Gif's are supported, maybe someone else can verify that.
What you can do is duplicate your prop, make sure Unique is selected in the modify section
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Then set each prop to a different texture file. Then on the timeline, change the Modify - Display from visible to invisible for the original one, and change the second prop to be visible at the same keyframe.
74% of original size (was 676x19) - Click to enlarge
It's not as easy as a Gif, but it works.
If you want it to change a lot of times, I wrote a Python Script for IClone 7 that does some similar. I might be able to convert it to IClone 8 if you need it.
Maybe someone else can tell you for sure if Gif's are supported or not.
Creator of the free website:
PixelDatabase.Net
A Free Online Text Based Image Editor
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