My "opening song" is one that has every light in the display in action at one time or another. I use it as the modern day equivalent of bulb patrol.
The quotation marks are because I don't have a start-up song, per se. Yes, someone has to go first, so in that sense you can call it the opening song, but I don't have it listed under the Startup tab - it loops along with every other sequence.
Do you always use a fixed timing grid? If yes, why? I'm a musical moron. For me, working with a beat-based timing grid is faster, easier and infinitely better.