Painting on procedural landscape material

Hello

I’m working with landscape and procedural landscape material from Epic, but here is only one layer “dirt”, not defined. When I’m trying to add/define it, I have procedural material lost, whole landscape is just dirt. Without layers I can’t paint on landscape and I can’t find solution. Any tips? I need few custom layers (roads, fields etc) and this procedural material together.

https://i.imgur.com/jstvYfU.png