I don't know how to make the textures import with the object. As far as exporting, it depends on what you want to do. If you're exporting a figure to render, use the Poser defaults. Also, make sure to import the .obj into Carrara as "facet meshes", otherwise you'll get a seam up the side of the figure. If you want to make morph targets, then you should check "include body part names" and "include existing groups", and uncheck "weld body part seams". When using Carrara for morph targets, I also make sure that auto-position and auto-scaling are turned off in the import dialog.