This isn't an uncommon scenario. My advice would be that you find a way to get some compensation, preferably in stock, for what you have developed while retaini

This isn't an uncommon scenario. My advice would be that you find a way to get some compensation, preferably in stock, for what you have developed while retaining only an advisory or part-time role so you can continue to tinker and work on what you love without creating pressure upon yourself to now co-run and develop a startup. That way you get some upside if it works out and you can participate and contribute but you're not responsible for its success or failure.