Re: How prevalent is RMG Wierdness?
 

Sometimes the RMG will screw up - however it should be obvious when this happens (most of the map is water).

I would never start a new game with a random map that wasn't pre-generated and looked over for big errors.

That said the RMG is very useful to generate lots of different maps - from which you pick and choose the best.

Re: How prevalent is RMG Wierdness?
 

I have also encountered similar RMG water/land weirdness intermittently. I entered a ticket (TICKET #: 1982) but the staff had no solution. Seems to occur more often if I generate the RMG with the screen minimized though that it occurs either way. Once I exit/saved and reloaded and the map was "fixed" though that does not work all the time. Happens to about 1 map out of 5 or so.
-Dave

Edit: Note Oceania on land and the funky centroid flag placements