Domiciliation Address for auto entrepreneur

My partner and I are currently in Morlaix and I am looking to register as an auto-entrepreneur.

My questions are:

1. We would like to get everything setup and then go long term cruising on our sailing boat.  Once we are set up can we stay tax resident in France even if we are not here during the year?  Our only physical home would be the boat so could this be achieved with a ‘domiciliation address’?  If so do you know of any near Morlaix?
2. My business activities are varied but all involve IT work.  So there is some affiliate marketing, some selling software as a service, some advertising revenue and some consultancy work.  Can all these activities be covered under a single auto-entrepreneur registration?  What would I put in the form under business activity?
3. In addition I would possibly be earning a side income trading crypto-currencies.  Would any profit from this be declared under the auto-entrepreneur scheme or as personal capital gains on the tax return?  If I was doing enough trading that it was considered a ‘principal business activity’ would this be covered under the auto-entrepreneur scheme?
4. My partner is a writer.  Would it make sense for her to register as an auto-entrepreneur or is there a better option?
5. If we used a domiciliation address would this cause problems when opening a French bank account?  Do you recommend any banks for the auto-entrepreneur scheme?

Many thanks and kind regards.