@MaleStranger: umodel supports only some basic materials layouts. But almost all games are usually customizing them in different ways, which can be somehow recreated only in third party tools (like blender, etc) according to material properties, which are available in separate files upon export or in the viewer in material mode (by pressing "M" and clicking on them). Visual issues with materials can be also caused by multiple UV sets used by mesh - not in this case though. It's also possible that a material may not use actual textures, but some scalar/vector values with masks for rendering, or shaders, or something else. Such complex tasks are out of scope of umodel and this forum.
I understand you, thank you. Not all games, multiple UV sets.
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