I have a mesh figure which rendered pretty well until I uv mapped it, after which it disappeared in the viewport (which has happened before). It was still in the Outliner, and I was able to delete and undo to get it back. I had to delete and undo every time I opened the mesh, until I rigged it, at which point the problem went away. I added a dress with a wrap and jiggle deformer, and was working on hair. Now when I open the project, the only way to render the body mesh is with Maya Hardware 2.0. Maya Software Render will render the dress, Mental Ray shows nothing. If I go back to previous saves it is so erratic that I am loosing track of what render engine renders what scenes. Nothing is missing from the Outliner. I am using Maya 2012 for Mac. I have deleted my preferences. I have tried reassigning materials. I have done searches for a couple of days now, but I cannot find a consistent problem or solution, although there are many similar issues.

Thank you.