1) Select Window->Open perspective->Other...->Prolog .
2) Open the preferences dialog from menu Window->Preferences->Prolog->Interpreters and press button "Add..."
3) Select the interpreter type to be configured (Swi, B or XSB) and press "OK" and "OK".
4) You can have several interpreters installed each of them of differen implementations (Swi, B or XSB) or two or more versions of the same implementation (Swi-5.6.50, Swi-5.10, etc) as long as each interpreter configured has a different name.
The interpreter whose check box is selected will be the default implementation to be used when you create a new Prolog Project although you can decide to use another during the creation of the project or once its created by:
1) Right click on the project and select "preferences".
2) Select "Prolog Build Path" and select the "Libraries" tab.
3) Select "Remove" to delete the Prolog interpreter associated to the project
4) To add a new interpreter to the project select Add Library...->Next->Alternative interpreter and choose your selection in the combo box, after that press "Finish" and "OK".