Back when I had my old computer, TTW was only stable if it didn't have many mods modifying the assets that TTW used, so basically if I was using any TTW exclusive mods, it would start getting unstable. I have a bunch of mods for my FNV setup on my current computer, It took me a long time but TTW will always be unstable with a modded FNV. But it's only enjoyable if you have more mods. You should check some mods like Zan Auto-Purge with purges dead bodies after awhile and stuff, also, check for any esps that could be merged as when I played TTW with esps that were useless and could be merged, it became more stable when I merged them, also despite FNV being an 8 year old game and the RAM limit is 4GB, you still need to check your system usage from time to time on your task manager, check which computer component is 90-100 percenting all the time, for me, it's my CPU. Also, check to see if this one door is the only door that has issues, if so, it could be a potential mod conflict. I'd also check FNVEdit to see if there are any mod conflicts with TTW. In the end, TTW unfortunately doesn't work for everyone. It took two computers to make TTW work on my FNV, I had bought FO3 GOTY edition just for TTW back in 2012 and that was when it was called something else under a different name, forgot what it was called and when I got my first gaming PC, didn't work on that one, installed in on my second gaming pc in 2014, didn't work, tried two more times before in 2017, I installed on my current rig and it JUST worked! The thing that made this one different was that I had installed my TTW first immediately after getting NVSE, some core mods to run FNV and not installing TTW later on AFTER getting all the mods I wanted.
So to summarize.
1.Check for mod conflicts via FNVEdit
2.Check your task manager and see which component is literally using ALL of its power.
3. Find out about some performance enhancing utilities that you MAY not know about and not have, if you don't have Zan Auto Purge, highly recommend it, it does use an ESP though.
4. Make sure TTW is at the top and all TTW exclusive mods or FNV mods that use TTW assets and thus have TTW editions are below them and/or are next to them.
5. Make sure this is an isolated incident to one door OR make a new save and see if it does the same thing. You could have uninstalled a mod on your current save and now TTW is not very stable because of that and so you have some lingering effects from a mod.
6. If all else fails, keep a memory of your mod list, uninstall FNV, reinstall FNV, and install TTW first! First, not second. First. This is the last resort. Only do this if you feel you cannot live without TTW and ABSOLUTELY want to try it without ANY hiccups.
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" Life is a beautiful and awesome process, awe-inspiring exchange of living things working together or against each other for each their own purposes." -Me, Matthew.