Enabling/Disabling for users
Enabling
To enable:
In the Main menu choose Accounts.
On the form that opens choose Users.
On the form that opens, select the user to whom you want to grant access to the module, and click Edit.
Example of Users form
In the user settings that open, go to the Access section and mark the checkbox opposite Can use PHP Composer, and click Ok.
Example of user settings
Also, when creating a new user, it is possible to immediately grant access to PHP Composer by marking the corresponding checkbox in the Access section.

Example of new user settings
Disabling
To turn off, unmark the checkbox Can use PHP Composer, as described in the Enabling section.