RPG Maps

I’ve heard and seem programs like Mappy that supoisidly can export a map with the tiles you made to your game in (arrays?). Well, ok my question is, so I could make tiles with a sprite editor like Tile Studio and set up my entire map in a program, then export it somehow into code? And what about the collision boxes, so I can edit this in the program or what?

Also as a rendering/gameplay question, if my gameworld were to be large, would it better to have the game where the entire map is exposed, or the break it up into “sectors.” Yet, I feel that breaking up the map into sector would break up the feel of the world.

If your map is too large then you will have to break up the map. However you can still make it look like one large map to the player by having the next map segment(s) pre-load while the player is on the current map segment. Thus when the play does move across the segments there is no indication to the player.