Thanks Leo, do you mind if I speak out loud about what I am going to do so, am I going wrong anywhere?
Next weekend, hire out a paint sprayer and fill with a watered down coat, cover the windows and spray away, stopping after ever wall to use the roller because of drips, then when the room is done, take the coverings off the windows and take out a paint brush and do around the windows, no doors/skirting etc in yet and proceed throughout the house. Proceed to paint the house the following week??? or should I leave it for two, cover up the windows again, the exact same way as I previously did with the undercoat and that is it?? do we need to do two undercoats, going to paint with a paintbrush in the end anyway, as I want the kitchen in 'Hessian' colour, the hall yellow and so on....