2. Unfortunately not – its something we have not been able to find a compatible solution for.
3. Not with the overlay style – you would need to use the Slideout option which we may be able to style similarly to the overlay. If you want to try that then don’t do #1 and set the off canvas to slideout and ill see what we can do.
4. Can do it with CSS if we were to follow step 3.
5. With the Overlay style you set it in Customizer > Colors > Off Canvas