One possibility would be to put the monster spawning code(or anything else you want to happen) in the repeatedly_execute_always.
Another way would be to make the walking non-blocking and setting a variable that keeps track of what hotspot has been clicked on. Then, you not only check whether the player is standing on a certain hotspot, but also if the variable is equal to the hotspot's ID.
Another way would be to make the walking non-blocking and setting a variable that keeps track of what hotspot has been clicked on. Then, you not only check whether the player is standing on a certain hotspot, but also if the variable is equal to the hotspot's ID.