Hi Jimi,
I think you have found a bug in the Xtreme 5 animated gif export.
If you select transparent background and preview your animation before exporting the objects are given a white background and is anti-aliased to white.
If you export the animation without preview the gif is anti-aliased to the colour of your background and can be used on a web page with that background colour.
I'll make a report to Xara about this odd behaviour.
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