On the left side a list is shown with all the currently selected Special Abilities for the culture or profession. Entries can be selected and removed from the list. On the right side new Special Ability bonuses are created.
Therefor different Special Abilites can be selected, which will show up under the tab titled 'Selected'. The player can select one of these Special Abilities for the character.
Optional a description for the bonus can be given. This description is shown to the user, when he selects the culture or profession at character creation. If no explicit description is given, one is created as an enumeration of all possible Special Abilities. For example if you select four topographys a description will be created as "Topography: Forest, Topography: Swamp, Topography: Steppe or Topography: Mountains". This is a little bit hard to read. In this case it would be better to use 'a topography' as description. You can test how this works by creating a bonus with description and without description. They will appear different in the list on the left.
If a Special Ability comes in different variants you can make it changeable by the player. For example you could select Armor Use I, and make it changeable. Then the player can select the type of armor the Armor Use applies to. Additionally you could enter 'a Armor Use' as description.