Why is the base colour map all black after import?

There may be the following reasons:

1. The normals of this material are reversed.

This usually happens with 3Ds max models.

You need to go back to the modelling software and check the normal orientation.

2. The colour mode of the texture is CMYK.

Currently D5 does not support images with CMYK colour mode.

You need to convert it to RGB mode in other software and re-import it.