I fixed the problems.
the store banner wasn't showing, so I tweaked the CSS to get rid of the "position: relative" tag.
The catalog item images weren't showing so I just converted the code in tpl_modules_main_product_image.php to remove CSS where it now uses straight HTML, as seen below:
Comment this line out, plus the associated closing </div> tag too:
<!-- div id="productMainImage" class="centeredContent back" -->
Then tweak the Javascript code:
document.write('<?php echo '<a href="javascript:popupWindow(\\\'' . zen_href_link(FILENAME_POPUP_IMAGE, 'pID=' . $_GET['products_id']) . '\\\')">' . '<br /><span class="imgLink"> Click image for larger view</span><img src="' .$products_image_medium.'" title="'.$products_name.'" width="'.MEDIUM_IMAGE_WIDTH.'" height="'.MEDIUM_IMAGE_HEIGHT.'" align="left" hspace="5" vspace="5">' . '<br /></a>'; ?>');
AND this PHP code too:
echo '<a href="' . zen_href_link(FILENAME_POPUP_IMAGE, 'pID=' . $_GET['products_id']) . '" target="_blank">' . '<br /><span class="imgLink"> Click image for larger view</span><img src="'.$products_image_medium.'" title="'.$products_name.'" width="'.MEDIUM_IMAGE_WIDTH.'" height="'.MEDIUM_IMAGE_HEIGHT.'" align="left" hspace="5" vspace="5">' . '<br /></a>';
That's it. Works in Firefox, IE on Windows, and IE on OS X.
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