These two have to be done in the animation file because it's being referenced to the lighting file.
1. Open the animation file for the shot. Go to Reference Editor and replace the main characters with the ones that have their extra hair removed. They can be found in the same reference folder, eg. Britney_del_hair.mb.
2. Remove key for their clothing options and change it to the one the shot is asking for.
Now you can create a lighting file.
1. Create a new scene and go to FILE>Create Reference. Select the animation file that is in the Final folder in your shot.
2. Look through the shot camera. Remove or hide anything that won't be seen.
3. Select the characters and create a new render layer from them. Select the background objects and create another render layer from them. Go to Layer Editor>Render layer>Layers>Create layer from selected.
4. Create Environment light for the shot. Go to Render Globals and change the render engine to mental ray. Go to Indirect Lighting and