Fog of war Interupting a player's move??

If players move their tokens through the dramatic lighting or fog of war, and they cross into a trap area or enemy's line of sight, is there a way to have them stop when they do to have the enemy attack or the trap trigger? Or do they just move past and you have to physically move their token back to that spot and say, "When you get here, X happens..."?  (Or even just while moving through simple fog of war in the free version?l

There is a script that can automate the "move back" part, but there isn't a way to prevent moving past events.

Ok