Hi. I'd like this forum to cover saving all variable types to a Spark.message().setMessageData() in cloud code and retrieving them in unity.

First i'll explain what I know. I know how to set up the message in messages tab:

Next you will need to set up the listener in Unity:

using UnityEngine;
using System.Collections;
using GameSparks.Core;
using GameSparks.Api.Messages;
using GameSparks.Api.Requests;
using GameSparks.Api.Responses;
using GameSparks.Api;

public class GameSparksManager : MonoBehaviour {
		ScriptMessage.Listener += GetMessages;
		ChallengeIssuedMessage.Listener += PlayerChallenged;
		ChallengeAcceptedMessage.Listener += ChallengeAccepted;
		ChallengeStartedMessage.Listener += ChallengeStarted;
	}
	void Start(){
		GSL = GameObject.Find ("Canvas").GetComponent<GameSparkLogin>();
		BI = GameObject.Find ("Battle Instance").GetComponent<BattleInstance> ();
	}

	public void PlayerChallenged(ChallengeIssuedMessage message){
			Debug.Log ("you have been challenged!!! " + message.Who);
//			Debug.Log (message.Challenge.Challenger.Id);
		GSData challer = message.Challenge.ScriptData.GetGSData("Challenger_Data");
		GSL.NewChallenge ((string)message.Challenge.ChallengeId, (string)challer.GetString("playerID"), (string)challer.GetString("playerName"), (string)challer.GetString("playerChar"), (int)challer.GetNumber("playerHealth"), (int)challer.GetNumber("playerMana"));

//		GetData (message.Challenge.Challenger.Id, message.Challenge.ChallengeId, "issued");
	}

	public void ChallengeAccepted(ChallengeAcceptedMessage message){
		Debug.Log ("CHALLENGE ACCEPTED!!! ");


		GSData challenged = message.Challenge.ScriptData.GetGSData("Challenged_Data");
		GSL.StartChallenge(message.Challenge.ChallengeId, (string)challenged.GetString("playerID"), (string)challenged.GetString("playerName"), 
			(string)challenged.GetString("playerChar"), (int)challenged.GetNumber("playerHealth"), (int)challenged.GetNumber("playerMana"), false);

	}

	public void ChallengeStarted(ChallengeStartedMessage message){
		Debug.Log ("CHALLENGE STARTED!!! ");

//		GSData challenged = message.Challenge.ScriptData.GetGSData("Challenged_Data");
//		GSL.StartChallenge(message.Challenge.ChallengeId, (string)challenged.GetString("playerID"), (string)challenged.GetString("playerName"),
//			(string)challenged.GetString("playerChar"), (int)challenged.GetNumber("playerHealth"), (int)challenged.GetNumber("playerMana"));

	}
	public void SpellCast(ScriptMessage message){
		
	}

	public void GetMessages(ScriptMessage message){
		if (message.ExtCode == "Challenge")
		{
			Debug.Log ("received Challenge Data");
			BI.UpdateBattleInstance (message);
		}

//		if (message.ExtCode == "Challenger_Data")
//		{
//			Debug.Log ("received Challenger_Data");
//		}
	}
}

 I'd really like to be able to access the challenge from my scriptMessage like I do from the built in challengeMessages. 

So far I only know how to set individual strings and ints and interpret them in unity using C#.

var spells = Spark.runtimeCollection("Spells"); // get the collection data
var thisChallenge = Spark.getChallenge(Spark.data.challengeInstanceId);
var ChallerPlayer = Spark.loadPlayer(thisChallenge.getChallengerId());
var ChalledPlayer = Spark.loadPlayer(thisChallenge.getChallengedPlayerIds()[0]);
var playerIDs = [];
var spellName = Spark.getData().spellName;
var beginCasting = Spark.getData().beginCasting;

playerIDs = [ChallerPlayer.getPlayerId(), ChalledPlayer.getPlayerId()];

var Spell = spells.findOne({
    "spellName": spellName
    });
Play();

function Play(){
    var challengedData = thisChallenge.getScriptData("Challenged_Data");
    var challengerData = thisChallenge.getScriptData("Challenger_Data");
    if(ChallerPlayer === Spark.getPlayer()){
        thisChallenge.setScriptData("challerBeginCasting", beginCasting);
        if(beginCasting === "true"){
    
         }else{
            challengedData.playerHealth = challengedData.playerHealth - Spell.spellDamage;
            challengerData.playerMana = challengerData.playerMana - Spell.manaCost;
            thisChallenge.setScriptData("Challenger_Data", challengerData);
            thisChallenge.setScriptData("Challenged_Data", challengedData);
        }
    }
    else{
        thisChallenge.setScriptData("challedBeginCasting", beginCasting);
        if(beginCasting === "true"){
        
        }else{
            challengerData.playerHealth = challengerData.playerHealth - Spell.spellDamage;
            challengedData.playerMana = challengedData.playerMana - Spell.manaCost;
            thisChallenge.setScriptData("Challenger_Data", challengerData);
            thisChallenge.setScriptData("Challenged_Data", challengedData);
            if(thisChallenge.getScriptData("challerBeginCasting") === null){
                thisChallenge.setScriptData("challerBeginCasting", "false");
            }
        }

    }

    var messageForm = {};
        messageForm.castingTime = Spell.castingTime;
        messageForm.challengerHealth = challengerData.playerHealth;
        messageForm.challengerMana = challengerData.playerMana;
        messageForm.challerBeginCasting = thisChallenge.getScriptData("challerBeginCasting");
        messageForm.challengedHealth = challengedData.playerHealth;
        messageForm.challengedMana = challengedData.playerMana;
        messageForm.challedBeginCasting = thisChallenge.getScriptData("challedBeginCasting");
        messageForm.message = "Hello World!";
    
    Spark.message("Challenge").setMessageData(messageForm).setPlayerIds(playerIDs).send();

And then retrieve it in unity using:

	public void UpdateBattleInstance(ScriptMessage message){
		currentChallerHealth = (int)message.Data.GetInt ("challengerHealth");
		currentChallerMana = (int)message.Data.GetInt ("challengerMana");
		currentChalledHealth = (int)message.Data.GetInt ("challengedHealth");
		currentChalledMana = (int)message.Data.GetInt ("challengedMana");
		enemyCastTime = float.Parse (message.Data.GetString("castingTime"));
		Debug.Log (enemyCastTime);
		if (message.Data.GetString ("challerBeginCasting") == null) {
			challerBeginCasting = false;
		} else {
			challerBeginCasting = bool.Parse(message.Data.GetString ("challerBeginCasting"));
		}

		Debug.Log (challerBeginCasting);
		challedBeginCasting = bool.Parse(message.Data.GetString ("challedBeginCasting"));
		Debug.Log (challedBeginCasting);

		if(isChallenger){
			if (challedBeginCasting) {
				if (!enemyIsCasting) {
					enemyIsCasting = true;
					Debug.Log ("Enemy Has Begun Casting");
					BWS.EnemyBeginCasting (enemyCastTime);
				}
			} 

		}else{
			if(challerBeginCasting){
				if (!enemyIsCasting) {
					enemyIsCasting = true;
					Debug.Log ("Enemy Has Begun Casting");
					BWS.EnemyBeginCasting (enemyCastTime);
				}
			}
		}

		Debug.Log ("BI isChallenger " + isChallenger);
		if (isChallenger) {
			BWS.UpdateStats (currentChallerHealth, currentChallerMana, currentChalledHealth, currentChalledMana);
			Debug.Log (currentChallerHealth + " " + currentChallerMana + " " + currentChalledHealth + " " + currentChalledMana);
		} else {
			BWS.UpdateStats (currentChalledHealth, currentChalledMana, currentChallerHealth, currentChallerMana);
		}
	}

But how do I save a retrieve GSData, ScriptData, JSONData, an entire Challenge object?

ScriptMessage.Listener = (message) => {
    GSData data = message.Data; 
    string extCode = message.ExtCode; 
    string messageId = message.MessageId; 
    bool? notification = message.Notification; 
    GSEnumerable<GSData> scriptData = message.ScriptData; 
    string subTitle = message.SubTitle; 
    string summary = message.Summary; 
    string title = message.Title; 
};

and:

I know of: 

GSData myGSData = message.Data.GetGSData("name of GSData key");

But how is this set in cloud code?

Please explain what you know in detail, do not try to simplify. I'd like this forum to become a reference for saving all variable types to a scriptMessage and retrieving and applying the data in Unity. Multiple implementation examples are appreciated.