The following are changes to caves for Miami 50x are vanilla, without mods. The structures in place are indestructible, and are to be treated as an actual terrain wall, any meshing or mesh attacking is prohibited.
RAGNAROK
MUSHROOM CAVE
(COORDS: LAT 10.6 - LON 23.8)
Main entrance lowered.
Main entrance (inside pov)
LITTLE SNOW TOP / GREEN OB CAVE
(COORDS: LAT 45.2 - LON 32.4)
Main entrance lowered. 
Second entrance blocked.
Snow Cave
(Coords: LAT 51.9 - LON 48)
Main entrance lowered/edited.
Main entrance inside POV.
TRIPLE WATERFALL
(Coords: LAT 28.1 - LON 47.7)
Second entrance blocked.

LAVA CAVE
(COORDS : LAT 19.4 - LON 65.4)
Outside main entrance.
Main entrance inside lowered.
HIGHLANDS CAVE
(COORDS: LAT 18 - LON 78.9)
Main entrance lowered.
Main entrance lowered (inside pov)
DESERT CAVE
(COORDS: LAT 85.8 - LON 51.6)
Main entrance lowered.
Second entrance blocked.
VIKING BAY CAVE
(COORDS: LAT 22.7 - LON 30.6)
Main entrance lowered.
Main entrance lowered (inside pov)
KURI CAVE
(COORDS: LAT 23.3 - LON 28.1)
Main entrance lowered.
Second and alternate entrances blocked.
GROTTO CAVE
(COORDS: LAT 26.2 - LON 26.9)
Main entrance lowered.
Alternate entrances blocked.
BURNING MISTS
(COORDS: LAT 35.6 - LON 49.2)
Main entrance lowered (inside pov)
Second entrance blocked.
MURDER SNOW CAVE
(COORDS: LAT 40 - LON 62.7)
Main entrance lowered.
Second entrance blocked.
ANCIENT WATERFALL
(COORDS: LAT 41.4 - LON 42.4)
Main entrance lowered.
Main entrance lowered (inside pov)
SKELLET CANYON CAVE
(COORDS: LAT 20.4 - LON 29.1)
Main entrance lowered.
Inside main entrance.