I just downloaded the new map Terra Swoop Force and started playing it, and everything was running perfectly for a while. But as soon as I put on the Elytra, and jumped into the caves, my game simply did not render any more chunks. I would fly to the edge of what was already rendered and then I would just be flying in an abyss, waiting to die.

Here's what hasn't worked:

1. Changing render distance (this just makes me fly into the "void" sooner)
2. Turning of ALL fancy graphics (Leaves, clouds, skies, lighting, etc.)