The parameters in the different modules are typically controlled by one of two types of controls;
Setting the value represented in a level setter control is accomplished by clicking on the '+' and '-' buttons to increment or decrement the value respectively. Alternatively you can click anywhere in the area between the '-" and '+' button to set a value quickly.
Switching items in the item selector is accomplished by clicking the arrows at either end of the item description. Note that the arrows may disappear as the first or last item in a set of items is reached. Alternatively the user may click on the label area of the item selector to see the full range of items which may then be selected from a pop-over menu.
For the purpose of astrophotograph then, your camera will have an ISO value that is optimal for this type of photography.
The 'Un-glow' feature attempts to reduce the halos around bright, over-exposing stars.
You can convert everything you see to a format you find convenient. Give it a try!