Composite Role should be represented in Role section, Role Configuration can be view and edited.
Created attachment 1203608 [details]
Created attachment 1203610 [details]
This has been recently implemented to certain extent. GUI is now able to list all Roles which are defined in tripleo-heat-templates (plan) and in Role detail section user is able to configure Role-related parameters as well as overview a list of services assigned to that Role and Configure each Service's parameters.
Creating custom Roles and Services and assigning them to a Role requires adding/manipulating templates and modifying roles_data.yaml The approach and options of doing this from GUI will be discussed at OpenStack Summit in Barcelona 
 Custom services docs (custom roles are TBA) http://tripleo.org/developer/tht_walkthrough/tht_walkthrough.html#composable-services-tutorial
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.
For information on the advisory, and where to find the updated
files, follow the link below.
If the solution does not work for you, open a new bug report.