You cannot store objects in array. Arrays in C2 can only store numbers or strings.
If i understand correctly, you will want to store object UIDs and use that as a reference to an object.
Also, i suspect (but am probably totally wrong) that you can avoid storing UIDs in arrays and with events (more exactly conditions) pick a group of objects, and then apply some actions to them.
I recommend reading how events work if you haven't read it, and of course look into Families and Containers for more advanced object picking.
Hopefully i didn't miss your question.
Also, i recommend getting used to manual, i do it almost daily.