Displacement problems

Good day . Today, faced with such a problem.


I see that your geometry contains an insufficient number of polygons. Displacement in EU4 have a maximum tesselation factor 10. And mesh must have pre tesselation. But, if you need use the low poly mesh, you can fake displacement with Bump Offset.

Look this tutorial

Besides using bump offset, if the texture isnt tiling on the corners the chance of these holes happening significantly increases.
If both sides dont have the same smoothing groups this can also increase chance of holes.