If your stock is worth $0, then can I buy it from you for $1? If you hold stock on a stock exchange that closes down every night, is your holding worth $0 over

If your stock is worth $0, then can I buy it from you for $1? If you hold stock on a stock exchange that closes down every night, is your holding worth $0 overnight while it's untradable? If you invest in a startup where you're not allowed to liquidate for 5 years, and then it eventually sells for millions, was it worth $0 for the entirety of those first 5 years? If your exchange only allows you to trade once every 16th of a second, is your position worth $0 during those 16th of a second gaps?