I only have the "ietester" ie6 version to test on but I don't get the behaviour you mention which is why I asked if others were experiencing the problem. Usually the ietester renders exactly the same as the real IE6 but occasionally can differ.
It all seems to work fine for me but the hourglass does flicker but then it always did in IE.
Did you try the fix from here?
Otherwise we'll have to wait for a real IE6 user to come along and test this but they are few and far between these days.
I've just checked using browsercam's remote service using a real ie6 version and the image does not disappear there either unless I change the browser preferences to "every visit" as I mentioned before. Once I change that setting then the slider does disappear and the other images also disappear when hovered as they are fetched anew.
That's about as much as I can do from here I'm afraid.