My first map, and it'll be a doozie.

[waldronate]

In this case the surfaces are externally connected to the sink so there's no major difference between the two. The river channels are flowing along the edge of really large elevation steps, too.

I have this strange suspicion that GeoTerSys would have a different opinion on the map with the large, nearly flat internal basin. Wilbur's first opinion was quite different and I had to do some unnatural processing to get internal drainage.

[Redrobes]

Well I am curious, a bit later when I have done my chores (sigh) ill run it up and see what it does to it. I have no idea because it really does not like extra flat areas. I have a mode to print out gradient in false color and where it goes red or black I know it will have an issue. I think here Wilbur will do a better job. I am expecting a large pool of water actually.

[Redrobes]

I got fed up with eating sweets so I had a bit of a play with this one. The results were pretty much as expected in that the grad map shows that where red is pretty flat and it is going to struggle to get long thin rivers here. Where its black its dead flat so its obviously going to pool water in that area. The land could exist but it would need a desert in that region to make it realistic. Anyway for fun here is the results from a quick run.

Its given me an idea for another parameter to try to fix up the local pools of water. I have obviously got a little problem there that needs fixing. The longer you run it the worse the pooling becomes.