If you're noticing these problems in the layout/explorer view, they are viewing artifacts only and will not effect the build output during a final build.
They exist because erosion and other algorithms are strongly sensitive to their surroundings, and so a given square of terrain cannot be fully treated properly without considering its neighbors first -- who also need to consider their neighbors, out to infinity. This makes it impossible to give a completely boundless world using the current algorithms.
I am trying out different terrain programs, looking for one that fits me. What I want to do is make EXTREME open worlds, like SkyRim or smaller open worlds like DA: Inquisition.
I was viewing the example files provided with World Machine 2.3 and noticed geometry errors. Lines going through the terrain into open space. Is there a way, preferably a simple way to fix these issues, maybe a better way to "sew" the geometry or link the vertices together?
If it helps, my hardware in my small server I used for testing this on is:
(ONE) GeForce GTX Titan v340.52
(TWO) Intel XEON 3.6Ghz (x2 8 Core (16 total cores))