Each process has its own instance list. To access the role editor, select the respective BPMN model of your service on the diagram pane and switch to the Attributes panel.

Click the icon next to Roles.

The role editor opens. The dialog initially contains an empty line to enter a role.

The handling of the role editor is already described in detail on Modeling Roles. In contrast to these explanations, the radio buttons to assign certain rights to the respective role are not available in the role editor of the instance list.

Example:

Jane Marple has the role ACME Manager and thus has the necessary rights to see the instance list.
Therefore, in the executed application, she will see the icon in addition to the icon (see Creating a Process Instance) when hovering over the service name.

After selecting the icon, the instance list opens and all open instances are displayed.

David Stringer has the role ACME Employee and thus has not the necessary rights to see the instance list.
Therefore, in the executed application, he will only see the icon to create a new process instance, but not the icon to display the instance list when hovering over the process name.