Thanks for the link. I was able to get the result you are reporting with just a grey block where the map should be in Opera 10. As a test of the map I have viewed the source and copied it to a static page of my own. When I view this page created from your source the map loads fine even in Opera 10. This indicates that the issue may be related to either something else you have on the page or something on your server. I think it is more likely something on the page that is conflicting with the map.
To further test this I added a base tag to the page and set it to your domain so that the resource links would point to yours. When I did this I tested the page again in Opera and the map displays ok, but when I view this page in FireFox it loads a grey box again.
This tells me that the problem is likely some conflict on the page, probably with some js code you have. As a test try creating a new blank page and apply the map on this page without any other styling or js code on it. Please post back and let us know how this works for you.
