Yes, you can adjust the heartrate zones. ANd ... you can do it on your PC and download the values to the bike computer. No intereference issues here. But sometimes you have to manually sync the pickups to the the bike computer.
Also, you have to get used to the concept that there are logs and trips. They are two different things. Logs have to be started and stopped in order for you to graph the data. And no logged data points do not contain cadence. But it will keep, min, max and average.