Unresponsive script error

I am having a problem with what is admittedly a complex GPX file. It will load properly to the animap and I can set various parameters such as the playback time and viewpoint with no problem. The map will also playback properly. When I choose "Markers" and "Edit Route" it will allow me to edit the route but when I end the editing I get multiple "unresponsive script errors". If I set Firefox to ignore the unresponsive script the editing will eventually close out but the track is truncated to the last portion of the original track and will not playback properly. I am using Firefox 11.0 but get the same problem with Google Chrome and Internet Explorer.