Many times the HTML or HTM files will display on your system but not on others. Try linking to the image itself. aka something ending in JPG or GIF. I also had someone posting items on eBay who said they displayed fine on his system, but they didn't on mine and others. I went and looked... he had all the "/" as "\" and worked fine because his computer was reading it off the cache.

That and what Archie wrote. If it doesn't show on the preview, it's not going to work for others. Once again, the cache can be the culprit. Looks fine here?