The idea behind it is basically the same as a standard cones class however the route is different. In a normal cones class at and ADS type show, you can't canter, you have to have your whip in hand etc. You have to go the correct/posted route, then you go back through it your way whatever way you want. Like if the posted route was 1-10 you have to do 1-10 first, then you can do 10,4,2,8,9,5,7,4,6,1,3 or however you wanted to as long as you do them all. Some horses prefer left turns, some right, so the driver does what the horse likes the best when choosing their route.
Scurry is about speed and obedience, you start in a "box" then go through the course then stop and halt in the "box"
I don't know about the errands class, we have a Town And Country course at our pleasure show and we have signs (think political signs that are everywhere) mailbox to put things into or get something out of, one year we had a truck with blasting music, 360 in a hula hoop silly stuff but stuff you might come across when out on the trail or traveling through town.
karen