It appears there is an issue with the "Time Since" condition when used with multiple sensors?
I have two motion sensors. When I try to test if the "time since" last event is greater than 15 minutes for both sensors (by checking the "all" checkbox), the condition returns false, even though both sensors' last events were more than 15 minutes ago. If I use the same condition on one sensor, however, the condition passes. Is this by design? I would think that regardless of how many sensors were being evaluated, if the last event on all of them was greater than the time specified the condition should return true!