Actually its true that textures in WAD file seems to be 16 bits, under settings i can see "1024x1024x16", but i tested with addFolder option and the result its the same and the settings of the texture that way appears the same 1024x1024x16 in texture manager.
Well i am not a 2d artist at all but i see the properties of the texture outside WED and bits depth is 24 and vertical / horizontal resolution 96 ppi.

What i am doing wrong here please?