Only times I've ever had DS presets (.ds, .dsa, .dsb) not apply is when  a) I've tried to apply it to the wrong item, b) when the file is corrupt.

With Poser format files there are only two things I can think of that would cause this, one is a typo in the code near the start of the file, but I haven't found one of those in a while so I have no idea if DS still fails to load them. For the second all texture references are in the 'shader tree' part of the material settings, and because DS doesn't read that part it takes it that there are no textures for it to load, you won't find this in any DAZ product (atleast I haven't found any) but I have found it in content sold elsewhere.