Select New/Agent contextual menu element on the Agent node in Repository Explorer. This will open the Agent Editor.
Give a unique name to the agent and check "Service Dispatcher" checkbox if you didn't already define a Dispatcher agent. There should be only one Dispatcher agent in a workflow. The Dispatcher Service will dispatch the tasks in the workflow that you will define.
As you suspect from their names, Service Event will evaluate the Events in the workflow and Service Execution will execute the tasks previously dispatched by the Dispatcher. Each of these Services run every XX miliseconds, as specified by the "Sleep Time" field in the editor.
If you want to install the Agent as a Windows Service you have to fill out the text boxes in the "Windows Service Properties" section, by specifying the name of the service, the path to the Agent installation directory and the names of the log files. The service/daemon log file(s) will be placed in the Agent installation directory and the Agent log file(s) in the <AWF_HOME>/logs direcory. Each of these log files is "rolled" meaning that you will have at most 10 log files numbered from 1 to 10, each of 5MB. Keep in mind that you have to specify only the log file names, not their paths.
After you save the Agent Editor content, you can install the service. This will add a windows service that you can start and stop.
To be able to install an Agent Windows Service from UI you should run the UI with Administrator rights under Windows Vista/7.