Landscape edit layers and texture painting issue

Hello folks !

I have an issue on the landscape, I want to paint material in different edit layers. And it seems that all the edit layers are kindof “additive” to each other.
See the screenshot here, when I paint 100% of the red layer on the edit layer “Top”, it seems that it’s not 100% here but half here, even with alpha set to 1.0 and the tool strengh to 1 as well.
It seems to work fine only with non weighted layers, but then I have other issues when sampling the terrain, and I really wanted to keep the weighted layer workflow anyway. I’m on Unreal 5.3.

Does anybody know if there is an hidden setting somewhere I’m missing ? :frowning_with_open_mouth:

Thanks !