To get started I downloaded some of Nvidia’s Omniverse USD samples. Opening those in InstaLOD Studio I can see the mesh just fine. I also see the various material names. However, all the materials render as grey. If I open the referenced MDL files (excerpt below) they point to the Omniverse default PBR shaders. I am guessing InstaLOD does not know how to handle those and so I am limited to mesh operations instead of texture baking?
mdl 1.8;
import ::state::normal;
import ::OmniSurface::OmniShared::emission_mode;
import OmniUber_Automotive::*;
import ::tex::gamma_mode;
export material Carpaint_01(*)
= OmniUber_Automotive::OmniUber_Automotive(
uvs_mode_01: OmniUber_Automotive::triplanar,
uv_scale_01: float2(1.f),
uv_offset_01: float2(0.f),
uv_offset_time_01: float2(0.f),
uv_rotation_01: 0.f,
triplanar_blend_range_01: 0.5f,
coat_roughness_image: texture_2d("../textures/noise_scratch2.png", ::tex::gamma_default, ""),
coat_roughness_channel: OmniUber_Automotive::r,
coat_roughness: 0.0599999987f,
....