A Shipwreck And A Crystal Cave | Let's Play Below Zero 18 

22:16 Sorry, the stasis rifle isn't in Subnautica Below Zero as a game design choice. :(

Just to let you know the biome with the purple crystals you are in at 20:15 is called the crystal caverns and it serves like the lost river from the original Subnautica in how it is an underground biome with multiple entrances throughout the map in the sea floor, and it also leads down into the fabricator caverns, the biome where I assume you beat the game, I'm not gonna spoil anything though.

12:31 Right the 2nd time, the Mercury II broke into 3 pieces, this is the middle and the first one you found in the purple vents is the back or stern.

A giant stick, sticking from the ground where everyone can see once repaired, it can block the sound And a new friendship comes to be But repairing it is not an easy task What do I need? you may ask that, what once flew, but now in depths lies what's now three, but one was once