You got the civil demand for the stop they made on you that day. Most likely, in reviewing your return history after the initial stop, they identified other incidents and entered reports on it which with some companies automatically generates a new CD.
Yup. Civil demands are a civil penalty for your actions and do not preclude criminal charges. I would not be surprised if they found additional incidents if they made a police report which may result in your getting a visit from the local constabulary. Many companies don't allow the LP staff to lie but I'm sure it happens.

