Thanks alot both of you guys, for the current time newt 's solution should work fine. Already implemented it and it's all good.
But I won't be able to use that solution as the project grows, I'll need to choose between layouts, backgrounds, sizes, etc.. so saving just these itens info is really what I want.
I was just looking for a way to optimize creating all objects one by one, with many creation events.
I'll try to make something using the instance variable, just not sure yet how to access it. Any help with an example? I mean, once I parse the JSON to an array each index will be an object, I know that all of them are "PlacedObjects(Family)", but how would I acces an instance variable of it?
Any way I can imagine now would be instantiating a PlacedObject(random), set it to the AsJSON string, get the type instanceVar, then destroy it and call another function CreateObject(type, layer, x, y), which returns instanced object UID.
Then pick PlacedObjects by UID using the returned UID and set its info to the AsJSON string from the array?
Any better ideas? This way I would be creating each object twice, not sure on how to use a while loop and have access to the instance variable there.
Btw I was using array with size(0,1,1)..thanks for clarifying that 99Instances2Go .