ok, understood. I solved my problem using the '(time)delayed switching off mobile data' method - temporary

.
Please let me one more question:
What is the main difference between the "Queue another event" and separated 'condition-action' event?
Queue another event creates a brand new event every time you run that action. Queued events are just like standalone, regular events except on three points (if more, someone point them out). First, queued events don't require conditions if you don't want to put any. If you don't give it any conditions, queued event's actions always run, with or without a wait. Second, queued events don't have any advanced settings that regular events do, except for the delay-and-cancel action. Took me a while to understand this but giving a queued event conditions and a wait is equivalent to setting delay with cancel in regular events. If you don't set wait time in a queued event however, the queued event never gets canceled. Third, unlike regular events, queued events run only once then disappear. So, if you don't give a queued event any wait but give it some conditions, the queued event will never be canceled and hangs around indefinitely until all its conditions are met, its actions are triggered, then the event will disappear. This variation in behaviors gives you a great flexibility (or headache) in setting up some sophisticated events in rather simple ways. Besides, you can't call a separate condition-action event from inside of another event. You can call a shortcut to another event, but if you do that, the conditions of the event that's called are all ignored and the event actions always run.
Inability of Llama to detect a process running in background seems to be a recurring problem for may people, especially with gps applications because Llama doesn't know whether gps is on either. The best I've come up so far is instead of turning gps off when an app stops or vice versa, I'd create a 'switch' that kills the app, gps, mobile data, and whatever else by a single tap. I'd figured, if you need tap tap tap to exit out of an app then gps, data, whathaveyou follow automatically, it would be as fast if not faster to tap on the kill button that takes care of everything.