Post Affiliate Pro allows you to customize the affiliate panel menu in an easy way.
If you wish to add or remove some menu items, then you have to navigate in the Post Affiliate Pro merchant panel to Configuration > Affiliate panel > Menus & Screens.
Adding a menu item is easy -- just simply click the "Add menu items" button above the list of menu items.
Afterwards, you can drag and drop items to move them in the menu to the desired position. You can expand the collapsed menu items (e.g. Promotion or Reports) by clicking the + button and nest the menu items under other menu items, or move items to a higher position (so the nested one would be moved to the same position as its parent menu item).
Do not forget to click "Save" to have your changes saved.
Removing a menu item -- simply drag and drop the unwanted menu item to the Trash section below the list, or click on the Delete (trash can icon) button. Again, do not forget to click "Save".