1st: While in Mastercam and go to the "SETTINGS" tab and go to "Machine Definition Manager" 

It will warn you that you are changing the Machine Definitions

2nd: Going through the "Machine Definition" go to the "Control Definition"

3rd: Under "Control topics:" choose "Tool" then choose to "Enable staged tool routines"

4th: Click on the check box to accept. It will ask if you want to save as you accept your way out, and ask if you want to replace your old machine/control definitions, just click "Yes"

The next time a program is posted it will have the next tool precalled.