Upon Initial Setup of the software you will be prompted for a choice of the two navigation modes:
No matter which Navigator Mode you choose here, you will always have the option to revert back. To do this go to your 'Tools' drop down menu and choose the navigation mode you desire. You can also change your default Navigation Mode by going up to your Miscellaneous drop down menu and select Maintain Settings and Options. Under the Misc. Tab you will see the first check box allows you to select which navigation mode you desire.