Booking start time in Appointments +

Hi there, I have setup my appointments + plugin to act as a booking system for 4 rooms in building. The configuration can be seen here: http://www.jamjosandbox.com/rubiconcentre/room-booking/ where the Services are time slots and the Service Providers are the rooms. However I have come across an issue. If you choose 4 hours for example from Step 1 of my page you can only choose a time slot from 8am to 12 and from 12 to 4 and 4pm to 8pm. This seems fine at first glance because my opening hours are 8am - 8pm so yes this seems fine!! However I have clients who might want to book 4 hours but from 10am to 2pm? so I need the ability for the user to choose the start time on their own accord. I do not necessarily need them to choose the end time for once they choose there time slot of 2 hours or 4 hours but they do need to be able to choose where their start time is? Is this possible? Why does it seem to start 4 hour time slots at 8am in the day by default, I need the user to choose. Everything else works great I just simply need this ability/feature of the user choosing their start time and not forced into based on their time slot for the booking. Anyway else of getting this working? For me this is a bit of a show stopper on this to be honest which is a shame so I hope there is a work around.

Also a heads up that the export feature does not export anything in the new version 1.3.1 - I mentioned this in another post.

Thanks for your time on this.