I'm a huge proponent of MapTool. If you can find a way to make the hosting work, I think you'll enjoy it.
That said, the first virtual tabletop program I tried was OpenRPG. I moved from there to Gametable and then MapTool, but I did go back to OpenRPG for one session when I was in a hotel and therefore unable to forward ports to my computer.
OpenRPG is a pain in the butt compared to MapTool, but this is in large part because you have to set up all of your images on a server before you can use them. Of course, this means that everyone then just connects to that server, which should address your problem.
It's worth a shot if you can't get MapTool to work.