A. You can cut the ties after it is planted. Make sure it is planted the same depth it was when it was dug up. It will help to stake it until it gets established.
The biggest problem is from watering too often and the soil not draining adequately. Ten gallons once every two weeks this time of year is enough.
You can spray the stems each time you water. It is thought that ocotillo can absorb water through its stems but not really proven. Lightly mist it when you water. You can use a spray nozzle set on mist.