That is a limitation (and benefit) of the d7II internal browser mechanism -- the issue is it is basically using the Internet Explorer engine to render the page, but it doesn't support much in the way of scripts, and supports no plugins or activex stuff.
This means it works when a system installed browser doesn't -- we used to use it for doing Windows Updates in Windows XP, when Internet Explorer wouldn't work, the internal browser pointed to windowsupdate.microsoft.com would always work and usually the updates it installed fixed the issue with IE.
This also means you'll see the issues you do with your website, etc.
I have an upgraded control for rendering web pages and that is actually coming in the next major release. I may be able to implement this particular feature early, uncertain. I have no idea what the new control supports as far as scripts and other website technologies, but I believe it does have an option (whereas the old one didn't) to suppress script errors -- unfortunately this won't fix them, just suppress the errors... Please address any replies or future topics to our new support portal, more info here: viewtopic.php?f=31&t=2377