The top of the Workflow Instances pane allows you to filter the results by workflow name, and by status.  The results of this filtering are displayed in the bottom pane.  You can use the buttons at the bottom of the pane to examine the workflow details, debug the process, resume execution, or terminate the process.

You can use the Queued Activation Messages tab at the bottom of the pane to display all messages queued and awaiting activation.

The Rules tab at the bottom of the pane allows you to create rules that control the behavior of messages associated with workflows.