I have observed this issue in many online flash-based games;
as I told you, if the flash player operated page is not at the foreground while loading, it may just not update the display;
for instance : I open a world in FOE (Chrome) and switch to Elvenar in the mean time (Waterfox) just to avoid being looking at a loading bar
when I get back, the display on FoE is unchanged (loading bar, but updates quite quickly);
maybe there is a problem with Opera;
I remember having used Opera for FoE 2 years ago, but I stopped because loading visited cities took ages...