Thanks everyone - looks like I've got a few options and some work to do.
Since the swf route gives this: "The following cannot be exported:Feathering, Group transparency.", I'll have to find a a work around for these and get up to speed on flash creation but it looks promising.
I shall also test straight image map exports to see how that copes. Thanks again Eric.
Anyone every done a fully interactive, zoomable, scrollable map with layers in flash and would like to share? Just kidding, although that would be the ideal in this case.