Do you have a <body> tag? This can happen if there is an html mismatch on the page. Maybe try moving the map to a new blank page to edit it and then you can move it back.
Your friends over here at WebAssist! These Dreamweaver extensions will assist you in building unlimited, custom websites.
These out-of-the-box solutions provide you proven, tested applications that can be up and running now. Build a store, a gallery, or a web-based email solution.