When using the Source 2 map import feature, some textures will not import at all. not even a basic "single base texture on principled bsdf/diffuse"
i assume this is the aforementioned "some shaders do not import properly" but i have a feeling it's a possible regression as i can remember being able to import most of the materials that are missing in this specific import without issue (only skins werent importing properly and would default to skin 1)
Blender View after importing models/geometry.

HLA Hammer View
if needed i can provide the VMAP and Compiled VPK/VMAP_C