Select a light and just click "Turn Off" if the light is on and "Turn On" if the light is off. To change the brightness of a light just click on the brightness slider.
To change the color of a light just drag the mini magnifying glass on one of the two color chart, or just double click somewhere inside a color chart. Similarly you can use the built-in Mac OS X Color Well.
You can access the bridge scenes by checking in the option on the Preference window.
A preset is very similar to a scene on the Philips hue iOS App. It will save the current state of your hue lights, when you click on a preset it will apply the preset to your lights.
Set up an alarm for all, a group or an individual light.
Clicks on Alarms and you can list the list of Alarms.