blender minor bugs

<leafw> bugs or minor issues: a file named anything_2.blend when I push '+' to
          increase to '3' it puts a '12' instead
<leafw> is this a know issue? 
<leafw> more: a material with fresnel 2.0 and Ztransp clicked does not render
          as transparent. I am using Shadow, EnvMap and Ray in the render
          settings.
<leafw> more: the render preview does not update unless one rotates/scales the
          viewer. If materials change, or lamp values, etc., the preview
          render remains.