The setup room isn't really appropriate for a machine-type model.

The basic steps:

1. Before getting into Poser, make sure that everything which moves together
   is part of one Group in the object file.  For instance, if your bolt has a main
   sliding part that's blue metal and a protruding handle that's wooden, and both
   of these pieces are rigidly connected, the blue and the wood should be
   distinct materials and both should have the same Group name.

2. Bring into Poser to get the scale and location right, as I mentioned before,
   and export.

3. Import the exactly scaled OBJ into Poser with all boxes unchecked.

4. In the material room, apply materials to the Usemtl zones.

5. Click on the grouping tool.  Hit the 'Spawn Props' button.  Close the grouping tool.

6. Hit the delete button to get rid of the original OBJ.

7. At this point you have the Groups still in their proper places, but each is
   now a separate prop in Poser.  Use the Hierarchy window to set up the parent-child
   relationships, with the "most central" thing (maybe the stock?) as the top parent.

8. Select the top parent and hit the Create New Figure button at bottom of
   the hierarchy window.  Poser will set up a CR2 in the New Figures folder.

9.  Get rid of the props and load the new CR2.   Adjust  the offsets (joint centers)
of moving parts, and resave in a better folder.

10.  Edit the CR2 to make the Tran parameters visible on any pieces that
need to slide, like the lever or bolt.  (Figures by default have only the rotate
and scale parameters visible.)   Also change all 'bend 1' to 'bend 0' in the
whole CR2, so the stock won't go all warpy and weird when you pull the trigger!

11. At this point you could also change the name of such parameters to
    make them easier to find ... maybe change the zTran on the lever to Slide,
    and the xRotate on the trigger to Pull.

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