The Arm & Bypass buttons on a device on the Vera UI don't do anything!
This is actually by design!
The Arm and Bypass buttons on devices in the Vera UI are only used by Vera, they do not actually do anything to the device itself, they won't physically arm or bypass it.
The buttons can be manually pressed from the Vera UI or their state can be set from LUA.
Vera then uses the state of the buttons, for example while executing a Scene or other processing logic.