the problem is with the latest ( v10 ) of flash, it breaks plenty flash applications at present and is the main version why I have stopped using flash for the time being.
Have you thought of alternatives to create slideshows for example mootools?
http://www.visual-blast.com/javascript/noobslide-mootools-image-slideshow/
http://www.electricprism.com/aeron/slideshow/
the links above should get you started on flashless slideshows
below is a link to completly remove flash from firefox and then do a clean install
http://kb.mozillazine.org/Flash
hope this is usefull
I would still suggest giving mootools a go, since flash always give problems lately
ps i cannot see any flash other than by looking in the source, so if it is critical to your business I would not put it in flash, and if it is only for decoration ... do you really need it?
the code from the last flash i used
www.sgtcompany.co.za
p.s I used the fullview domain for property afterwards
<object classid="clsid

27CDB6E-AE6D-11cf-96B8-444553540000"
codebase="http://download.macromedia.com/pub/shockwave/cabs/flash/swflash.cab#version=6,0,40,0"
width="720" height="291">
<param name="movie" value="Flash/header.swf?button=3">
<param name="quality" value="high">
<param name="menu" value="false">
<!--[if !IE]> <-->
<object data="Flash/header.swf?button=3"
width="720" height="291" type="application/x-shockwave-flash">
<param name="quality" value="high">
<param name="menu" value="false">
<param name="pluginurl" value="http://www.macromedia.com/go/getflashplayer">
FAIL (the browser should render some flash content, not this).
</object>
<!--> <![endif]>
</object>