If I understood the first one right, you want an event to be triggered within an large area without having to make an excessive amount of events, right? I know a way this could be done through scripting, but it's simple to do with events aswell.
First, you'll have to make 4 events, 3 of them should be empty, the forth will run through parallel-process. You place them so that each of them have a parallel with another, I'll show an example;
2
1-----3 The number of tiles you leave between them will become the area where the event will be triggered.
4 # parallel process
When you've set them up, you'll just have to make a couple of variables(with the parallel process event ofcourse). Do it like this;
Variable1 = Player Map X
Variable2 = Player Map Y
Variable3 = Event1 Map X
Variable4 = Event2 Map Y
Variable5 = Event3 Map X
Variable6 = Event4 Map Y (you see I set them up so it'd be accurate to how i placed them earlier.)
Next, make an Conditional Branch, the event id's will be the same as shown before.
Conditional Branch: [Variable] Player Map X] > [Variable] Event1 Map X (larger than)
Conditional Branch: [Variable] Player Map X] < [Variable] Event3 Map X (lesser than)
Conditional Branch: [Variable] Player Map Y] > [Variable] Event2 Map Y (larger than)
Conditional Branch: [Variable] Player Map Y] < [Variable] Event4 Map X (lesser than)
Show Text Message: (whatever you want to write)
Control Self Switch: A = ON
And there you go, hope it was simple enough