Movarth's lair being a butt and crashing

[MysteriousBug]

So I finally got Skyrim, after recieving a giftcard from my mom. Things were going fine and dandy, when I finally figured how to fight effectively. I figure out, I am way too low level for the main quests, and start doing side quests to level up a bit, and get some better gear possibly, etc. I am completing "laid to rest", go to Movarth's lair to complete the next bit, the mob hadn't arrived yet, so I went in with Lydia, the killed the spider, killed the thrall, killed the next thrall, moved near the the"descent", instant crash to desktop, no warning, no nothing.
I then load up the game again, same thing repeats, I have tried doing things a few different ways, but nothing seems to work. I have also tried, to find a solution to this problem, but nobody elseseems to have experienced it.
The game shold be patched to latest version, I have all the DLC, because I got legendary edition, and I have no mods installed. The settings are set to medium because that is what it recommended. The only settings I have touched are the key bindings, I think, maybe sound.
Any help would be greatly appreciated. Thank you.

[Hamsterbytes , bits and nibbles]

The unofficial patches for each DLC you own from the Nexus site should help with these problems. The nexus is free to join, but makes you think you have to pay. Just skip the pay section and finish joining. Also download LOOT, a mod order program to put your mods in the correct order : http://loot.github.io/