Thank you for the reply!
I might be able to make the concurrent mode work for me. I would designate Zone 1 as the master. Does that mean I could just run all my valves as mini individual programs? Would OpenTimer be capable of operating my valves as I have detailed below? Obviously, a 1 minute delay between Zones is not ideal, but is preferable to water hammer!
05:00:00 – Open Zone 2 valve
05:00:05 – Open Master valve
05:15:00 – Close Master valve
05:15:05 – Close Zone 2 valve
Then just do the same thing for the next valve one minute later:
05:16:00 – Open Zone 3 valve
05:16:05 – Open Master valve
05:31:00 – Close Master valve
05:31:05 – Close Zone 3 valve
Thanks again!