Lightmap of Lod1 on custom dirt blocks

[Skyslide]

custom blocks which uses stadiumdirt as only material uses also only one uv layer: 0, lightmap
with only lightmap i have this results:



lightmap is compatible with lod0, there is not really a difference:


with useless basematerial layer i got this result:


i added basematerial layer to all terrain blocks and map looks now as it should, no random black faces