EeMm. The way the mix/master file is created and processed is shown in the tutorial videos, but basically you need to press Record in mixdown mode to create the file in the first place. If you're happy at this point, there's no need to go any further - the file is there waiting for you to either play it (but only in mastering mode with all mastering effects turned off!) or to copy out to your computer (note that the Export process is not relevant or required to do this as it only applies to individual tracks). The mastering phase is optional. but if you do want to use the mastering effects, you have to press Record again (in mastering mode) in order for the mix/master file to be re-processed and overwritten with the mastered result. I doubt if running through this process with the mastering effects turned off would affect the quality, but there is only one mix/master file (and it's already been created during the mixdown phase) so there's no point. Also note that if you're happy with a 'bounce' result, then you don't even need to enter mixdown mode - just export the bounced track.