That's an artifact of the compression algorithms the jpg format uses. If you use a png export from Fireworks, though, you can upload it here. You can't use the working png, though. You have to actually export it rather than simply save.

You should not be seeing artifacts in gif, though--it's lossless. There might be a problem with the way Fireworks does the conversion.

I really like your mountains. I tend to overdo the mountains, putting more symbols than I need on the map.

I think instead of using "call-out" lines for the labels, you would do better to simply place the labels in close proximity to the icons. Also, the labels that cross solid black lines are a little bit obscured. Especially Crater Fountain and Goblin Cave. If you put a semi-transparent, light-colored object behind them they'll stand out better. I don't recall off the top of my head if Fireworks has any glow effects that can be applied to text, but that would also work.