Problem with Painting Materials

So I have been doing my first tutorial on EU4 and i came up with this problem where I try to paint my landscape. but when i try to use my 4th material it refuses to compile. It shows the compiling shaders thingy but on preview the landscape remains as if it had no material on it. What could be causing the problem? And how may i fix it? Thanks in advance.

Some solution to resolve this problem - user less then 4 layers. Landcape layers work correct only if you use 1-3 layers, 4 or more layers make landscape painting default graymaterial as well. I don’t know at the moment its bug or not… Maybe some layers downgrade for more perfomance.

Set your texture samples to use “wrap”. Screenshot - 4e6e387f3dd482aba1c74b5f4e6e1364 - Gyazo