Hi, I think your issue is not IE8, but rather a missing hot-spot image that the viewer is trying to find in the following location and which is missing in this path:
I see. Then this is the IE8 issue we fixed in May specifically in our OpenCart integration. Here's our reply that I copied from the OpenCart comments section on our 360 viewer extension page dated May 15th 2013. I checked the file on your server and looks like you don't have this fix.
@robynice: good news - we fixed the IE8 issue (thanks again for your tip!). The new zip includes the fix but if you don't want to reinstall, you can just do the following:
1) Find this file in your current installation: catalog\controller\module\wr360\wr360hook.js
2) Open it in edit mode and navigate to line 15 that looks like this: var newHtml = "<div id='wr360PlayerId'/> \
3) Replace this line with this: var newHtml = "<div id='wr360PlayerId'> \