Hello there @ArcaneGel2!
The "zero width or height” is usually tied to a corrupt FBX, or missing content inside, like an assigned texture. There are also calls to missing smoothing groups, and payload. Let’s test some methods for resolution in Blender:
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Check the Shading tab, ensure that an image file is tiend to the Image Texture node, and check for any empty or broken nodes
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Make sure any texture under use is saved somewhere in your machine (Image > Save As)
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When exporting again, enable “Apply modifiers”, enable “Smoothing”, and set it to either “Face” or “Normals”
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Also, check “Export Normals”, “Export Tangents”, and use FBX 2014 format