Remove "Participants and Group Based" access selection when groups are not used

EDIT: This is reported to be fixed in Collaborator 11.2.

Currently we have no way of preventing users from selecting "Participants and Group Based" access level for Collaborator reviews, and because we are not using groups, selecting this option locks out all users from opening the review record, requiring an Administrator to go in and change the record back to "Participants".  All we can do is tell users not to mess with that field - ideally, we would have the option to remove that dropdown altogether from the form because there's only one option we want to use.