1.6.0 regression: Loading mesh_decal.mt materials is broken

[philipl]

I happened to try importing base\characters\main_npc\takemura\g1_001_ma_gloves__takemura_decal.mesh today using Blender 4.1 with 1.5.5.2 and it worked fine. I then realised I had not updated Blender or the add-on and so I upgrade to Blender 4.2 and 1.6.0 and then repeated the import. While it did not print any errors, the resulting imported material was broken, with a bunch of unconnected nodes in the shader graph.

I then repeated with Blender 4.1 and add-on 1.6.0 with the same broken results. Then I downgraded the add-on to 1.5.5.2 again and it imported correctly.