A world I made appears to have become corrupted while on realms, in ways I have never seen before. While the world is still playable for the most part, several peculiar bugs have arisen such as:

Players can move through water as though it were air.
Lava uses the water textures.
Lava and water do not interact with each other.
Anvils cannot be used.
At least one chunk causes the game to crash when entered.

I've put a considerable amount of effort into a project build in this world and am not okay with this kind of glitch arising from a service I pay for (minecraft realms). I have attempted to attach the world, which remains glitched when loaded in singleplayer, to this issue, but it appears its filesize is too large to attach and it is my only proof this is real. How can I attach my world?