thats about right the babyseat has to be hard against the car seat in order to be effective. IT will press hard against the seat best thing to do is get covers to protect the seat. Either use a clean set of floor mats or get this one
http://www.amazon.co.uk/Prince-Lionh.../dp/B000083GHY
Use this as protects the seat back and base as well as seat base front from foot prints. SOme seats like the Jane Exo you extend the ISO fix mounts from the base and then push the seat into the car seat and lock in place. THis is to avoid twisting in a crash.