To edit the preferences for the project set use the menu "Window > Preferences" and select "Project Sets" on the left side. On the right side the following page will be shown.
The list shows the defined path variables that can be used to define preferred project locations. Variables can be added, removed or edited with the buttons beside the list.
The option below allows to specify whether a project will be refreshed before being replaced. This may be useful if the automatic refresh in Eclipse is disabled and files are changed by external programs. Otherwise there may be messages that warn about files that are not synchronous to the Eclipse workspace when a project is replaced.
To edit the preferences for the project set editor select "Project Sets Editor" on the left side. On the right side the following page will be shown.
With the checkboxes the default behavior for the project set editor can be set.