(don't forget to enable watch mode, otherwise the rules won't be active. Tools > Settings > General Tab > Watch mode = ON)
To sum up what these rules do: calls can only be answered by hardware keys (since once the phone rings, screen is immediately locked [even if phone is set to Silent mode]). Once the call has been answered by hardware keys, the screen is unlocked. If the call has not been answered (by passively letting it ring out, or actively by rejection), the screen is unlocked.
watch for ---> windows windows title ---> ActiveSync To excute if the windows is opened ---> wireless --> BT on To excute if the windows is closed ---> wireless --> BT off To excute if the windows title is changed ---> BT off To excute if the windows is activated ---> wirless -->BT on