Helo, I am keen on this program. But about a week ago, I find out that this posibility (Utilities/ Map Servers) didnt work. Instead of a wanted map, I can only see error message "open layer is undefined". It is same on both my computers. Several weeks ago (middle of July) it was been OK.
I dont have selected any overlays. Its same in all maps (usualy I have selected OSM mapnik, but if it din't work, I tested several other). I am sending you screenshots with comments (because some of messages are in Czech). Since I wasn't successful by sending attachment, I give this here http://www.uschovna.cz/en/zasilka/BA859R62UWGN294S-5EZ//?set_lang=en (the file will be stored till 9.10.2014)
I've make the same thing with your coordinate, resolution and map type and works well. Have you made any changes to mapservers file? However you can try to follow manual instruction at paragraph "In case of error". Tell me if you solve.