your drop out is not completely locked, its more of your wheel sliding against the rail as well as you dipping the front end down and completely straightening your arms, a duster or a "Derek duster" is done by doing the same motion but your peg and wheel are against the rail rather than your...
you ride a steel peg and do what is called a "peg chink" where you do a powerslide on the beck end and scrape the peg on the ground, obstical, etc. It has to be a steel peg though, aluminum will not spark it will just wear the peg down unevenly
yes, I'm extremely picky about how my scooter feels so I'd say I feel a lot more comfortable riding in general when it feels exactly how I want it. If its not then I just feel miserable while riding
your video is for you to make, use a song you enjoy to listen to that fits the riding and style of the video. If the sole purpose of your video is too please others than its not a raw representation of you and your opinion, which is the main purpose of editing your own video