I have been thinking about this for a while no, and I have no clue yet. We haven't heard anything similar from anyone else. But, you can hopefully help us figuring it out.
It's very likely that it's a javascript issue, and you should then be able to find the error for us.
1) Go to
http://project-gc.com/ using Chrome.
2) Press F12 to bring up the developer console. Click console in the top of it.
3) Click the menus to get to the LiveMap (Tools, Live map).
4) If you get any text in the developer window we would like a copy of it. It is likely that it contains some form of error.