Have you tried checking out the "trouble shooting" panel in the BrowserPlus Config Panel? This is a new tool in 2.1.6:
Program Files -> Yahoo! BrowserPlus -> Configuration Panel.
If this is not present, it suggests you have 2.0.6 installed. We've had some upgrade problems from 2.0.6 to 2.1.6, which should be resolved now, so IF you have 2.0.6 installed you could always try uninstalling from add/remove programs, and then visiting the install page again.
Look forward to hearing if any of this resolves your problem, lloyd
finally, if you still have trouble accessing these files in a couple of hours, please complain here loudly. Our ops has said they'll be able to respond even quicker with your (public) ip and the host that bp.yahooapis.com resolves to for you.