Can you elaborate on how you want to manually open/close valves? Do you need a separate switch for each valve? That would involve a lot of wiring.
Firmware 2.1.7 supports a Program Switch to be connected to the rain sensor terminal. This allows you to use a switch to trigger Program 1 to run. So if you want to manually test all zones or something, you can use the switch to manually start Program 1. But it won’t allow you to select a specific valve to run.