it is posible, you'dd need to load the peace of island you're walking towards and unload the piece your walking away from.
Have you ever played GTA: Vice City? each seperate area (Vice Port, Escobar Airport, Fort Baxter, etc.) aren't all loaded at the same time. There all loaded like described above. (The loading inbetween the islands is for the low texture version of the island (the one that the speedyer ones of us have experienced manny times))
For objects, your should just use as far as the camera can see (plus a lil so it doesn't just pop-up)
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