The Lot Sync Timer keeps the time early enough that the paperboy/girl is not generated before you have a chance to create one yourself. This is the first NPC I usually create in a new neighborhood because I often start thinking about other things and forget to set the clock back. The options for skintone, age, and gender are on the Townie & NPC Maker itself - perhaps
this post may help answer some of your questions.
ETA: Sara's post deals specifically with spawning a Grand Vampyre but the steps are basically the same for creating all NPCs. I don't think it's mentioned in that post but if you spawn a Sim you do not want, DO NOT SELECT KILL. This creates an unlinked, crap character file that does nothing but take up space. Instead, exit the lot without saving and re-enter to try again.