Would I be right in guessing that in the FM document the
images are full size as FM is for printed output but the
requirement from you is to display a thumbnail that becomes full
size if clicked?
If so that effect can be achieved but not from functionality
built into RH. What you need is some javascript and each of your
images in the two sizes required. RH will be set to display the
smaller image. You need some javascript that displays the full
image when the user clicks the thumbnail or hovers over it. You'll
find that sort of script by Googling.
You can make the thumbnail a hotspot and create a link to the
large image but that may not work the way you would want.
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