Bryce will NOT load transmaps and bump maps automatically for the simple reason that Poser doesn't export them. If you peer into the .mtl file that Poser writes you will see that the transmap is not referenced. So either you have to hack the .mtl file some way or (much better) load the transmap and bump map separately in Bryce. You do NOT need to pass the model through UVmapper. Save yourself some time.