Hi Makigirl,
here are some images showing my setup. These are the manually made LOD0 UV coordinates for which I use a lightmap resolution of 64, so having a background grid in Blender of 62. Having no overlaps, no wrapping and enough padding. And try to keep islands large enough but have seams at corners to avoid bleeding artifacts.
The mesh is as follows
Rendering results with LOD0: left image with reduced static lighting level scale and changed parameters as recomended, but it is the scale parameter, that cleans up the result. Right image is the exact same mesh, just using default settings instead.
And another render result, with same mesh just scaled by factor 4 and default settings as well. Lower left are the original 2 mesh instances (LOD1 now). This shows, that the model size / level scale is the cause of main troubles.
