Custom map system?

I am making a game with very large maps. I don’t want to force users to download them, as they would take up a lot of space. I would like to make it possible for players to choose to download a map. How could I have Unreal Engine dynamically load an unbaked map (or other asset file) ingame? If this is impossible, is there some way of custom-baking them and then having Unreal Engine detect them?
Thanks!

Hi ilangleben19,

Due to the large volume of questions and comments concerning the Engine, we did not have a chance to respond to your post at the time you submitted it. However, if you are still interested, this feature was added in engine version 4.8, which you can see within our ‘Cooking’ section for the Release notes on our Documentation.

4.8 Release Notes

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