n-Track Studio v4.0 and later has built-in support for burning wave files to CD audio tracks. You can open the "Burn to CD" window with the View/CD Burning menu command. You can then drag (for example from the recently used wave files window) or import the wave files to be burned into the tracks list window. You can also mixdown a song and directly burn it to CD checking the "Burn audio CD track" option in the mixdown dialog box.