kaiko you can take the Ajax.LastData and load it into the Storage object using the Merge Table action. When you're done you can dump the JSON string to text object to see it.
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The storage object is 3 dimensional so if your JSON object is one dimensional it will create top level names of "default".
Example
Storage.Get("default","default","myfield")
Think of it as a C2 Array that works more like a C2 Dictionary