Creating New Group Sets Permissions Automatically on All Users / Cannot Deselect

I was experiencing what I think is the same issue – make sure not to select a WordPress role and it will not do this. Basically if you assign your new group a “Subscriber” then all who are subscribers will be in that role

Yes, had the same behavior and solved it as you need to set the role within the groups (UAM) and not for each user anymore, brillant and totally makes sense ! love this plugin.