Hi Sunny,
Welcome fellow Kiwi

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I also sell on TradeMe as well

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To answer your question, have a look at this post:
http://www.mympxplayer.com/viewtopic...ight=quicktime
Try converting your Quicktime files if you still can't get it to convert using the AMV Convert Tool still after following that post.
You can use:
RAD Video Tools (video file converter)
Let me know how u get on.