Main Tracks are an easy way to create lighting shows quickly and efficiently by allowing you to control all of the fixtures in a Venue Tab from this single Control Track.
For example, if you created a pink to blue fade in the Main Track, regardless of the lighting fixtures used such as LED Par Cans, Moving Heads, LED Tubes or LED Panels all will display the same pink to blue fade created in the Main Track.
Main track information is also standard across all of your venues. This is helpful if you work at a number of spaces or even if you land a gig at an unfamiliar venue on short notice. For any such venue, simply set up a new Venue Tab then input the appropriate lighting fixtures and as you will see the Main Tracks you have previously created will automatically be applied to the new Venue when working with those same audio files.
Not to worry though if you want more customization, you can override these Main Tracks via the individual Fixture Control Tracks or Fixture Groups in the workspace; it's up to you how in-depth you want to get.
Creative Tip: Try building up a library of Scripted audio files over time. Creating Main Tracks for your audio files is a great way to do this as it ensures you will always have some custom lighting to use at any future gigs.