I do not want to tell you that problem is on your end but i think it is true a bit as well.
I face same issue when my internet is working a little slow. Nords have more flash content than any other game of Plarium so it will take time.
Additionally as you mentioned you cleared cache etc. so your browser does not have any cache stored which means it have to reload all elements from the server which will take time as well.
Can you please check your internet connection & see if it is working normal.
After that open your game & once your stronghold & all the animations are fully loaded, go to map & leave the browser there for a while. It will work :)