Thanks nolgroth and Steel General.

I noticed the pixellation after posting the map, but it was lateish at night and time for sleep.

I had resized it from a smaller 600x600 map. There's still pixellation in that one too though. There's something going on in the background from all the playing around with the settings that I did while drawing it. Of course the fact that I was blindly playing around without any thought to scales, effects or final appearance would have nothing to do with that now would it?

I'm going to keep plugging at it--with the knowledge of how I'd like to the finished product to appear--with some additional cosmetic improvements.