Status Icons are a good way to mark creatures on the map affected by some effect. It's also a good way to mark enemies with a certain combat challange. You may add or subtract any number of status icons from the status.zip file.
Typically each image in the status.zip file is a PNG of 100 x 100 pixels.
You can create any folders in the status.zip file and place the images in some arrangement, however, when applying a status icon to a creature it will list all alphabetically.
For Example, here's what the status.zip file contains:
And, here are the Status Icons in d20Pro:
