Landscape Normal Layers not working correctly


I’ve got some issue with the landscape material system.
I created five layers and I use these with color maps, normal maps and ambient occlusion maps.
So I’ve got 3 layers blends in my material.

Always when I use more than 2 normal map input in the layers blend node I have some behavior where the landscape material isn’t rendered in parts of the landscape. Like shown in screenshot 1.png the default material is used (in the specific painted section of my landscape). Only when I paint some “working” layer over the painted parts the material is working again.

It happens when I use height blending or weight blending. The first layer is always set up as alpha blending.

(see the screenshots)

Do you have some ideas how to fix this?
Currently I’m working without normal maps and everything is working fine.
All textures do have a resolution of 2048x2048.
This problem occurs at UE 4.15 and 4.14

Does it have to do with the fact that I cannot find a checkbox in the material editor to say that the material is a landscape material. In earlier versions I had to check a checkbox “use with landscapes” (or something similar). I couldn’t find this checkbox anymore.

Hello, Sir. I think i know how to solve your problem. Try to change in your master material every SamplerSource of TextureSample from “From texture asset” to “Shared: Wrap”.