I've said it before and don't want to be a killjoy, but I don't think this will be quite the exhibit being hoped for. I have seen Colobus groups at many zoos- a lot of the time they spend being inactive, often huddled together in a group high up & resting, while any windy or bad weather will send them indoors- if they are allowed the access. So periods of classic activity- jumping/leaping/feeding etc, may well be very limited I fear.