Check your file size, if the file is really large then Poser can bog down and take a much longer time to render, also make sure to click on the advanced tab, if you're using higher than I think PropPack to make sure that you don't have conflicting nodes selected. Also check transparency settings. There are some good texture tutorials here as well as at Daz3d that can help you with creating textures. There is also Mat Pose Edit that I think is still freeware to help with the Mat Pose file for the new texture.. http://koti.mbnet.fi/~ilaripih/MPEHome/

-DR