Firstly, the whole idea of there being a paper roll is so that you can hide everything but the model, including the floor...

I'm gonna go through this shot by shot to explain myself better.

#1 - Total write-off. She's nowhere even near in the frame properly, she looks like she's gurning, her body is wracked, and her feet are grey from the really odd post edit you've done on it.

#2 - The pose is ok, but you should be higher up looking slightly down to accentuate her head and shoulders rather than her waist. You should have told the model to smile and again, the post edit is not flattering but that could be because the actual image is over exposed.

#3 - This is actually really nice. The floor works in this one and although all the blacks are purple, it doesn't look completely outlandish. The model's feet are still a strange colour though, remember to selectively edit. The position and pose of the model is natural and suits her well and your composition of the shot is strong.

#4 - This is really unflattering to the poor girl... Around her mouth looks brown and it's blatently obvious where you've liquified or whatever you did on her arms. Not to mention you've cloned out whatever it is on her forehead you didn't like and yet left her stubbly armpits and porous neck untouched.