This circuit is designed for someone in dire need of a new challenge. Especially when that new challenge has a side effect of awesome upper body development. Best completed in a gym on quieter day when equipment is readily available for hogging.
Complete the full circuit as many times as you can within 30 minutes. The rest time is entirely up to you, even if that means during a set. What counts is the reps. You cannot move on to the next exercise until all reps have been completed.
Use the amount of weight given as a general guide, if you feel that it is too heavy/light for you, by all means give it a change. Though, if you manage to complete 5 rounds with the weight given, you definitely deserve a reward. A cupcake, a new car, or something.