Add the ActiveController

Management/ActiveController.gd

@@ -0,0 +1,35 @@
+extends Node
+
+var current_active : int = 0
+
+
+func _process(_delta):
+	the_connecting()
+	the_pausing()
+
+
+func the_pausing():
+	# iterate through the children, allowing only the current active node to run
+	for i in len(get_children()):
+		get_child(i).pause_mode = 0 if i == current_active else 1
+
+
+func the_connecting():
+	# iterate through the children and connect up the child_finished method
+	for i in len(get_children()):
+		# don't connect the signal if it doesn't exist
+		if not get_child(i).has_signal("finished_active"):
+			continue
+		
+		# don't connect the signal if already connected
+		if get_child(i).get_signal_connection_list("finished_active") == []:
+			continue
+		
+		get_child(i).connect("finished_active", self, child_finished())
+
+
+func child_finished():
+	# designed to be called from a signal
+	current_active += 1
+	if current_active >= len(get_children()):
+		current_active = 0

Management/ActiveController.tscn

@@ -0,0 +1,6 @@
+[gd_scene load_steps=2 format=2]
+
+[ext_resource path="res://Management/ActiveController.gd" type="Script" id=1]
+
+[node name="ActiveController" type="Node"]
+script = ExtResource( 1 )