Another thing to remember when using imported objects (Poser or any other 3d object) - the texture size should match where the item is in your picture.  If the people will only be in the background, then there is no need for a 4000x4000 texture map!  Learn how to resize them or use something like SkinVue.  

If you have 2 GB and do some thinking, you can get multiple figures in your scene!  If you have 1GB, then you'll have to work harder and smarter, but don't think it's impossible.  There is more then one way to do things!

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