Hi
I have 4k heightmap, I can export this as one map fine but as soon as I try to export it as a 4x4 tiled set for UE4 using the settings they suggest it screws up the tiles, there are huge height variations and if I open the one Heightmap in Photoshop and and import the tiles to overlay them as a check the tiles do not match the heightmap , the values are different and so is the form of the terrain slightly, it is almost as if tiles have altered Erosion or something.
I cannot post this as it is a commercial project, But I can PM it to you.
Erosion has problems over tiled boundaries. You may have to set your tile blending amount to 100%. You’ll lose a little but of detail from the blending but it’ll ensure your terrain looks nice after export