jPCT loads texture coordinates and names from 3DS as well as diffuse colors (but only if there are no textures assigned). Everything else will be ignored.
If the file contains diffuse colors but still comes out black, have a look at the log output. Diffuse colors can exist in two different formats. The file itself doesn't contain any information about which one it uses, so jPCT has to guess. However, some exporters create diffuse color information that i couldn't make any sense of.
If this is the case, this will be written to the log.