You can delete the preview material if there is a line in the OBJ file titled usemtl Preview (search/find usemtl Preview, select, delete), deleting the material Preview within the .pp2 will cause the prop to load invisible, It's necessary for poser. Best to set up your materials in an external modeler, Load the OBJ in poser, save as prop, edit the resulting .pp2 in a text editor, delete embedded geometry, and add reference to folder Geometries which will contain your original OBJ. I never set up materials with the grouping tool.

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W10 Pro, HP Envy X360 Laptop, Intel Core i7-10510U, NVIDIA GeForce MX250, Intel UHD, 16 GB DDR4-2400 SDRAM, 1 TB PCIe NVMe M.2 SSD

Mudbox 2022, Adobe PS CC, Poser Pro 11.3, Blender 2.9, Wings3D 2.2.5

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