title: Xcode simulator different to preview
body: <p>I am drawing an interface in <em>XIB</em> files using <em>xcode 7</em>, everything looks fine in the designer, and in the preview for all my targeted devices.
  However when I use the simulator, or install to my <em>iphone 5</em> the layout changes completely, colours are lost, controls are bunched up and/or completely moved.</p>
  
  <p><strong>I have no constraint errors or warnings</strong>, it does not make sense.</p>
  
  <p>I am also using <em>autolayout</em>.</p>
  
  <p>any help is much appreciated.</p>