My recommendation is to first get the easystar behaviour for tilemaps if you are using a square grid like AW did. I use it myself for my projects and its fantastic. It is possible to recreate its functionality with events but believe me it is faster to have a plugin/behaviour for this rather than do it via events. And by faster I mean it will use less CPU power.
You can also get the move to plugin as well and see how the demo of easy star with move to works (found in the topic below):
Basically you need two things. You need pathfinding functionality with diagonal movement disabled (easystar can be set to do that) that returns a list of tiles describing the path (easystar does this, accessing it might be a bit tricky at first). You also need something to move a unit along the path (after the tile is clicked/selected).