What's the size in pixels of the larger image? There is a hard pixel limit in the Flash Player.
I'm trying to load an image (through url) as a groundoverlay on a google map. I use a different url from the same domain like (http://www.lamma.rete.toscana.it/models/marevento/wind10m_A_3.png) it works perfectly but with the one I need (in the code) it doesn't. The only difference is the image dimension (27.7k the one that works, 477k the one that doesn't)