Rob Norris - 2018-04-09

I don't know much about MacOS.
I assume you have file write persmissions for the /Users/user/Library/Application Support/Viking/viking-maps ?
Otherwise you'll need to change the default Map folder location.

Secondly try using the OpenStreetMap (Mapnik) map type as this is less likely to run into server provided Tile limits.

Thirdly you can try running Viking with the command line parameters '-Vd' which will print out more debug information which can help pinpoint the underlying issue.