Are you serious that you would blame the manufacturer for a problem on an eight year year-old RV when you are not the original owner? They have no obligation and I would have no expectation that they would fix it for free! I have owned 2 Grand Design 5th wheel trailers and they have fixed everything that I asked for within the warranty period and a few things outside the warranty.
It looks like Bad Design, er I mean Grand Design does not care about their customers. It would be a shame if people who have this trailer with the "bad design" windows all would start a campaign to get them fixed by the company, the power of the internet is something you should not mess with. As a mater of fact it would be an even bigger shame if just everyone started asking them what they plan to do about their faulty windows. Because who knows maybe all of us were thinking about buying one right? I don't imagine their contact info is too hard to find.