Exposure Adjust. Allows you to modify the scene as if it had been shot at a higher or lower F-stop.
Gamma Adjust. Allows you to adjust for different monitors or playback systems.
White Point Adjust. Lets you select the spot in an image that you would expect to be white in real life. To get the true-to-life color you want, click on the small preview image; when the cursor changes to crosshairs, click on the point you want to define as white. The plug-in will then appropriately adjust color for the rest of the image.