If you pick the material in TM and check the bitmap fields of the diffuse, do you see any file name?
I see that your bitmap name is very long. This could cause an issue as Windows is quite bad at handling very long file names, and maybe during the export, they are truncated, causing TM white=unknown name.
possible workarounds:
- Do a material substitution, Material Substitution Workflow | Twinmotion Documentation | Epic Developer Community
- or pick your Revit material in the TM scene, apply it to a cube stored/hidden somewhere in your scene, and apply correct bitmaps (you can copy and paste them from existing library material fields). At each reimport/update, if Twinmotion ask you about material conflict, answer ‘use scene material’. they then should be consistent.