At the bottom left of the screen in the editor, there is snap grid options. There you can edit how much snapping you want between each piece. There is also an anchor button there, it toggles whether you want to snap the objects to the grid or not. The monster in the room, requires some scripting. It needs to have path nodes that direct the monster.
This is how you script it, in a function you create, when either the player interacts with an object, collides with an object, or just a plain timer from the time the player starts playing, or just plainy automatic.
void OnStart()
{
Function01();
}
void Function01()
{
AddEntityPatrolNode("MonsterName", "Node01", 2, "");
}
In the editor, you must go to the "area" category on the right side of the editor screen and in the dropbox once you click it, go find "PathNode", and place it where you want the monster to go once the function is taken in effect. The "MonsterName" is the name of the monster in the editor, the "Node01" is the name of the path node for the path node in the editor, and the "2" is the time between each point it goes to. So yes, you can add more than one path node and patrol node code line. Once the monster completes going to each path node, the monster will dissapear by itself. I hope this has helped you. Good luck.