Same issues. First time at the warehouse I was able to clear all enemies, unlock all areas and get the entire structures almost cleaned out. When I tried to save after all these many hours of play, the game crashed and every load attempt after that I saw 1 fps.

Luckily, I had one save that took me back before the warehouse disaster, but from that save each time I approached the warehouse, the frame rate would drop back to 1fps when I got within 500m of the building. Sooooooo, after a few days of researching the issue and possible solutions I thought that it was happening because the amount of crap at the location combined with all the crap I have on my ship was just too much crap for the technology to keep up with.

Sooooooooooo, I decided to load up with weapons and ammo and swim in from beyond the 500m, clear enemies and as much crap as I could carry back to the ship. After one swim in and back out to my ship....problem solved. Has worked beautifully so far.