I have the same problem with Safari, but I just learned to cope with it. Basically, when the script has to load something it just sits like that and no matter how long you wait, it just keeps loading. Examples:
-when you change the time of departure of a new route it keeps loading, while loading, you can still select another time of departure, and then it will work
-when you choose an aircraft type on new routes, again, keeps loading; let's say you choose 737-600, and it just loads, while loading, you select 737-700, and 737-700 will become the option; then you can select again 737-600, now it works
-when you try to select or load a list of airports to open a new route to
-when you create a new seat configuration (e.g. you choose standard business seat, screen disappears, background still shows, and it keeps loading)
Basically, when you can still select another option, it's fine, but sometimes a blank screen (background only) comes up, and then you have to refresh and start again.