Answered: Polyester Rug Gripper and String Pulley

Is it against any competition rules if our team uses a polyester/vinyl rug gripper that rolls on VEX wheels, pulled by non-official polyester string attached to a motor as a pulley system to transport stars on the robot? I’ve seen multiple teams use the rug gripper such as here:
but I’ve never seen it used in a flat sheet moving form. Also, is the string event legal to be used and cranked shorter or longer on a gear connected to the motor?

Part 1: “polyester/vinyl rug gripper”

Here’s what the VEX EDR product line has that meets that description:

So this would be a legal part, as well as mats that are identical as per <R7b>

Part 2: String/Rope

<R7k> specifies the allowable rope for robot construction.