In general, assigning Primary Responsibility is
optional in SLIM-Collaborate. But since ONLY the user with primary
responsibility can check/uncheck the project’s private project checkbox,
private projects MUST have a primary responsibility designation. Before
making a regular project (without an assigned user in the Primary Responsibility
field) private, a user with Full or Manage Projects permissions must add a user
to the Primary Responsibility field and save the project. Once the project
has been saved with a valid user in the Primary Responsibility field, the
private project checkbox will be enabled for the user with Primary
Responsibility only. Other users who gained access to the project via the
project’s user access list can see the private project checkbox, but editing of
the checkbox will be disabled.