Hi everyone! 
We're a party of 8 people (2 families) from Spain who will be visiting WDW from Aug. 13 to 19th. We're staying at Disney's All-Star Movies Resort, and have Hopper tickets for 6 days.
My family consists of 4 adults (1 room), and the other family consists of 2 adults and 2 children (1 room). Each family booked through different travel agents here in Spain, so we both have a different reservation number.
I just recently found out about MDE and its advantages. I've been reading a lot online about it but haven't found answers to my questions yet.
I obviously want to make reservations for the 8th of us (FastPass+, book a table, etc) and not just my family, or myself as we will be visiting the parks together. So, my questions are:
1. Can I create 1 MDE account and link both my family and the other family (friends) reservations there? (that way I'd skip the "invitation" step) Or do we have to create 1 account for each family and then link then compulsorily?
2. Who should create the MDE account? Can any of the adults create it or does it have to be adult under whose name the reservation was made?
One last question (non-MDE related), how can I ask for our rooms at the hotel to be adjoining or as close as possible to each other?
THANK YOU FOR YOUR HELP.

We're a party of 8 people (2 families) from Spain who will be visiting WDW from Aug. 13 to 19th. We're staying at Disney's All-Star Movies Resort, and have Hopper tickets for 6 days.
My family consists of 4 adults (1 room), and the other family consists of 2 adults and 2 children (1 room). Each family booked through different travel agents here in Spain, so we both have a different reservation number.
I just recently found out about MDE and its advantages. I've been reading a lot online about it but haven't found answers to my questions yet.
I obviously want to make reservations for the 8th of us (FastPass+, book a table, etc) and not just my family, or myself as we will be visiting the parks together. So, my questions are:
1. Can I create 1 MDE account and link both my family and the other family (friends) reservations there? (that way I'd skip the "invitation" step) Or do we have to create 1 account for each family and then link then compulsorily?
2. Who should create the MDE account? Can any of the adults create it or does it have to be adult under whose name the reservation was made?
One last question (non-MDE related), how can I ask for our rooms at the hotel to be adjoining or as close as possible to each other?
THANK YOU FOR YOUR HELP.