It's correct, no one is seriously discussing other apps besides GR3 because there really aren't any... To your issue with IE11, it's pretty obvious it's something within your computer as there are many others using the same combination with no issues. That unfortunately doesn't help you right now, but it is what it is. I assume you've taken the steps of disabling all antivirus applications to test as they often set up internal proxies for internet connections which may be the root cause. The issue doesn't appear to be systemic, but is in your specific environment. It sucks, but good luck to you in finding what's wrong. It seems highly doubtful it is a GR3 issue.
On the possibility of an HTML/javascript viewer, it's possible but would require server resources to decode the base data so will be fairly expensive to run on the back end of it so you'd be dealing with a subscription model.