I get this a LOT too in p6. As far as I know there is no way to get rid of all those texture listings from what I've heard, it has to do with the sizes of the textures too. For instance, you use a v4 character that has a 4000x4000 texture, and all the clothes are 4000x4000 and the scene is also that size, kaboom, my poser chokes and dies. when I have to cancel I get back to the scene and all textures are gone from the way I currently view.  I've resized some of the clothing that has large textures and that helped me.  I also lowered my bucket size too down to like a 16? Plus there are times I render out pieces and put them together.  I think vendors forget not everyone has mega computers. :( 

You can try lowering your max texture size too, that may help a bit.