The first column lists the channels in the document

The Dot size is displayed in dots per inch. Screen printed dots often range from 35 Lpi to 60 Lpi. 50 Lpi is a good, printable dot for most applications.

The Screen angle determines the orientation of the dot screen applied to each channel. for Screen Printing it is best to rotate the angle off the standard 45 degree rotation to avoid interference patterns from the Printing mesh or textile substrate. For multi color printing it is also helpful to rotate color sets to avoid Moire patterns.
A good approach is to use:

22.5 degrees for White and Yellow channels.
52.5 degrees for Red and Orange channels
82.5 for Blue, Green and Purple channels
52.5 for Black and Gray channels

The dot shape options are Ellipse, Round and Line. For most halftone applications an elliptical dot is preferred. For special effects and custom applications both the round dot and the halftone line are nice options.

determines the final resolution of the output document. For quality halftone representation at 50 LPi, a resolution between 600 and 720 is recommended. The default resolution is 720 PPI.

The preview function applies a gain curve to each channel during processing. This provides the option to see how a print may appear on press.

If the Print preview option is selected, the Preview PPI overrides the Output PPI, allowing a lower resolution file to be processed. This speeds up the processing of the preview file.

the amount of increase applied to each channel by the curve.

Provides a dialog which allows an adjustment curve to be applied to each channel during processing. Transfer functions are used to adjust for gain that occurs during the imaging process.

When the script has completed it will display the Success dialog. Checking the about box displays information about the script.