All topics with the same SortOrder value are sorted by Topic Type, then by alphabetic topic title. This groups together all methods and properties and then secondary sorts them by topic.
There are two ways to set the SortOrder value, which overrides the default sort order by assigning a value to the SortOrder field. Higher numbers mean higher in the sort order:
The sorter works by assigning specific SortOrder values to all existing topics in increments of 10 (this so you can insert topics at a later time). Once you use the sorter all topics in a subtree have sort order values, so adding any new topics will cause them to be automatically dropped to the bottom of the list. You can revert to the default sort order using topic type and topic name by clicking on the Default Order button.
Unless you click on the Update button none of the changes made in this form will take! When you're sure the topic order is appropriate click Update and the new topic SortOrder values are updated on each topic and the tree is updated to display the new sort order.