I think we can actually work out what the objects are ourselves to a degree - it's clear that they are gameplay files. The global layer contains:
- A saved game associated with the world (which we're exploiting to get sims in).
- Information on all the sims in the world.
- Information about the state of objects that are not on lots (for example, if you have an uber dive well off lot with settings applied (you can CTRL SHIFT + click off-lot tomb objects from build mode in CAW), then cleaning the global layer strips away its settings).
- Stores of outfit resources.
Obviously CAW can't render these as they're not all models. The watermelon and various random objects that they appear as are just misinterpretations of the gameplay content.
None of this stuff is essential to making an unpopulated world, and the game will fill it all in if you clean the global layer.
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