Hi,
1. Set-up RSVP's for your games, and in the RSVP section you can enter an event limit - eg. 5 x players. You can then as an admin select your 5 x players as a 'yes', then enter anyone not playing as a 'yes' after the 5 are selected, and those who are 'yes' after the 5 x limit go onto a 'waiting list'. This will be reflected by an orange label in their app, and in the yes/waiting section they'll be listed in 'waiting'. So this might work?
2. It's not possible to enter 'attendance' with a note/comment at this time. It's only a tick. And at this time you also can't enter a reason for replying 'no'. You can create RSVP questions, but these only come into play if a member replies 'yes'. So unfortunately we don't provide a solution for either of your needs at this time.
Kind regards,
Craig.