Action Queue: I need help on the finer details...

So after watching Sean Middleditches video about Action Queues, I started to implement my own version of them, but I am running into some snags, and I am hoping people could shed some light on how to iron it all out.

First, my GAction object class:

Code (csharp):

1.  
2. #pragma strict
3. public class GAction extends MonoBehaviour{
4.     public var previous:GAction = null;
5.     public var next:GAction = null;
6.    
7.     public var aList:GActionList = null;
8.    
9.     public var blocking:boolean = false;
10.    
11.     public var paused:boolean = true;
12.    
13.     public var complete:boolean = false;
14.    
15.     public var trans:Transform;
16.    
17.     public function Init( _go:GameObject ){}
18.    
19.     public function OnUpdate( _dt:float ){}
20.     public function OnFixedUpdate( _fdt:float ){}
21.    
22.     public function OnBlocked(){}
23.     public function OnUnblock(){}
24.    
25.     function OnComplete(){}
26.     function Destroy(){
27.         aList.Remove(this);
28.     }
29. }
30.  

Here is the GActionList

Code (csharp):

1.  
2. #pragma strict
3. public class GActionList extends MonoBehaviour{
4.     public var first:GAction = null;
5.     public var last:GAction = null;
6.     public var go:GameObject = null;
7.     public function Start(){
8.         go = gameObject;
9.     }
10.     public function Add( _a:GAction ){
11.         if( null == first ){
12.             first = last = _a;
13.             _a.next = _a.previous = null;
14.         }
15.         else{
16.             last.next = _a;
17.             _a.previous = last;
18.             _a.next = null;
19.             last = _a;
20.         }
21.         _a.aList = this;
22.     }
23.     public function Remove( _a:GAction ){
24.         if( first == _a ){
25.             first = first.next;
26.         }
27.         if( last == _a){
28.             last = last.previous;
29.         }
30.         if( _a.previous != null ){
31.             _a.previous.next = _a.next;
32.         }
33.         if( _a.next != null ){
34.             _a.next.previous = _a.previous;
35.         }
36.         _a.trans.gameObject.Destroy(_a);
37.     }
38.     public function RemoveAll(){
39.         while( first ){
40.             var action:GAction = first;
41.             action.trans.gameObject.Destroy(action);
42.             first = action.next;
43.             action.previous = null;
44.             action.next = null;
45.         }
46.         last = null;
47.     }
48.     public function Update(){
49.         var action:GAction = first;
50.         while( action != null ){
51.             if(false == action.paused){
52.                 action.OnUpdate(Time.deltaTime);
53.                 if(true == action.complete){
54.                     Remove(action);
55.                     action.OnComplete();
56.                 }
57.                 if(true == action.blocking){
58.                     break;
59.                 }
60.             }
61.             action = action.next;
62.         }
63.     }
64.     public function FixedUpdate(){
65.         var action:GAction = first;
66.         while( action != null ){
67.             if(false == action.paused){
68.                 action.OnFixedUpdate(Time.fixedDeltaTime);
69.                 if(true == action.complete){
70.                     Remove(action);
71.                     action.OnComplete();
72.                 }
73.                 if( true == action.blocking ){
74.                     break;
75.                 }
76.             }
77.             action = action.next;
78.         }
79.     }
80. }
81.  

So basically I add this GActionList to a game object, and then I can add arbitrary 'GAction' objects to it through script. It all works fairly well, no complaints.

The problem is, how do I manage this when I add multiple types of actions, which are different in implementation, but similar in functionality?

For example, the default 'MoveTo' action just takes a position, and moves the user to the position (point and click). Now say I want to implement a 'ChargeAtTarget' action, which should remove any previous 'MoveTo' actions. The 'ChargeAt'Target action would have a cool down timer, take an actual GameObject instead of a position, etc.

Now say the user used the ChargeAtTarget action, but then tapped elsewhere on the screen, interrupting or cancelling out the Action. How do I setup these conditions and consequences?

I also am implementing a String based EventSystem, so I am able to Add and Remove event listening along with this...

Does anyone have any reading material, or examples, even pseudo code, on how to work with a system like this? Essentially, every action the user can do is one or more GAction, such as RotateTowardPosition, MoveToPosition, ChargeToTarget, Axe2HAttack1, etc.