The sills are a pain in the **** really. They aren't held down by any screws. They clip into the sideskirt and are held down by double sided tape. The aluminium s3 plate is also held down by double sided tape and is not attached to the actual plastic surround. Depending on the age of your car, it's likely that you will fracture the plastic at some point when trying to remove them unless you are very careful as the plastic deteriorates with age. Use a heat gun or hairdryer to warm the tape up as this should help you remove them easier.
As for the rear cards, they are held in place by clips but you need to unscrew a few parts first to take them off IIRC. The seatbelt cover needs to be pulled away, think it is clipped at the top and has two torx screws at the bottom and it should pull away. Lift up the trim along the rear window too as this overlaps the door card. Then use a flat bar or something to get behind the door card and gently force it away from the car to unclip it. Once you get one clip released then you can work your way around the card. I can't remember if that is everything but should help you for now.
