Problems with Script Lag and/or CTDs

Some spells, abilities or MCM options are, by necessity, more script intensive.
If you find your computer slow to process, or perhaps you are already running several other scripted mods, then disabling the following features might help speed up your game (especially those with a *):

* Light Level Penalties - disabling light level penalties will prevent the script from updating every 5 seconds when you are outside during the day (it checks to see the light level and determines if you can use some abilities or not)
* Sun Damage - disabling sun damage while outside during the day can really help speed up your game; the script updates every 5 seconds to apply the proper damage if you are in direct light
Praestare Sanguinare - removing this ability, or not using it at all to turn others in vampires, may help speed up your game;  normally a small script is applied to each person you turn so they maintain their vampirism upon cell reset and so they seek out victims when they hunger - a lot of turned NPCs could mean a lot of tiny scripts adding up
Deflect Light and Shadow - to maintain "perfect" invisibility that lets you attack while remaining invisible, a script attached to the spell constantly refreshes your invisibility; your game might slow down when using this ability
* Vampire's Sight - disabling or not using this spell will prevent your game refreshing all nearby feeding victims every 5 seconds; they normally get highlighted with a glowing red shader - a lot of nearby victims could slow down your game
* Reveal Auras - disabling or not using this spell will prevent your game refreshing all NPCs every 5 seconds; they normally get highlighted with different colored shaders according to type - a lot of nearby NPCs could slow down your game




If you suspect scripts have become screwy, or maybe you installed a new version over an old version and duplicates are polluting your save, you can try these helpful tools:


Save Game Script Cleaner by Hadoram


http://www.nexusmods.com/skyrim/mods/52363



SE SkyrimTools -- Script Cleaner and more by Mark Fairchild






If scripts in your game (and all vampire mods are by necessity script intensive) are running slowly, try the cleanup method below.  It require patience, but it can help fix your game.  Remember to disable and completely delete my mod before following the advice listed below.

Copied from here:  http://skyrim.nexusmods.com/mods/31675


Rotaur, on 1 April 2013 0:00:36, said:


I can confirm the great efficiency of SKSE cleaning procedure method. It really WORKS! However the process requires PATIENCE, for it may take several hours. In my case it took practically the entire day. Nonetheless, the method is perfectly safe and simple and serves people with older Windows (read below). Before that, I reached the point that my game became unplayable due to constant CTD's; my save file grown to the size of almost 88Mb! Earlier running game freezed every minute for 5-6 seconds and finally every freeze becomed CTD. In my desperation, I was about to use the Flexcreator's drastical method. Unfortunately I've come across unpleasant surprise: the Flexcreator's bat files don't run on WinXP. Happily, some people (Talos bless them) mentioned on this very thread about new SKSE version incoming, which offers salvation - Talos bless SKSE creators! I hope you don't mind the reminder of the procedure:
  
1. Get at least the 1.06.08 version of SKSE http://skse.silverlock.org and install it.
2. Go to your Skyrim "Data" folder and create the SKSE folder (if you don't have one already)
3. Open your Data\SKSE folder and create SKSE.ini file (if you don't have one already)
4. Write (or paste) the following lines to opened SKSE.ini file and save changes (close the file): [General] ClearInvalidRegistrations=1
5. Run the game using skse_loader.exe (it should be located directly in your Skyrim folder)
6. Load your saved game you wish to cleanse and the process should start automatically (don't expect any notification - this is shy work)
7. You may open console and type: ClearInvalidRegistrations This command is not necessary, but can ensure you that you have the value of 0
8. DISABLE YOUR AUTOSAVE options and DO NOT USE QUICKSAVE during the cleaning process
9. It is recommended to move immediately your character to the safe interior location, like Breezehome or Test Hall ("coc qasmoke" console command) and make new save at once THROUGH CONSOLE COMMAND "save nameyourfile" (for example: save washmydirt)
10. Make sure you have disabled or uninstalled any survival mods which could kill your hero over time (hunger, thirst etc.)
11. Let your hero stay and do nothing (Yes, just leave him/her be standing still) - you should probably turn off your monitor and go on with your everyday activity It is also a good idea to release your followers and remove all equipment from Dovakhiin's body.
 
It is also up to you how many mods you wish to uninstall prior the entire process. The point is to feed the game with as few data as possible. How to check it works? Just make another save after few (or several) minutes (REMEMBER TO SAVE ONLY VIA CONSOLE COMMAND). Exit the game also via console command (qqq). Compare the size of older and newer save.ess file - the newer one should be a little smaller. Run the game again (ALWAYS VIA SKSE) loading last save (just hit "continue") and make new save (VIA CONSOLE) after... let's say an hour of automatic floating of a camera around our poor bored hero. REMEMBER: do not move away with some menu opened! It only works during an "action" - in this case patient and humble standing still and letting the camera float around. Quit the game again (console "qqq") and compare: the newest save.ess file should be after an hour significantly smaller. And continue with larger intervals: the good solution would be leaving the game opened before you go to bed (just turn off your monitor and... sweet dreams). Check it up next day and continue procedures depending on your available home time until new save.ess cease to be smaller.  Remember also TO NOT OVERWRITE THE SAME SAVE. Just make always a new one.
 
I have managed to drop my save file size from 88Mb to about 6Mb! Yes, this is not some dumb advertising of loosing weight or such. The process is slow and gentle, yet consistent and effective. It took me approximately 20 hours of "live action" total. The final result? I can play the game normally and experience no freezing. And yes, it did not cleanse my dirt 100% I must admit. My papyrus script logs still contain some dramatical information, however of incomparable size. Previously I got log files of up to 15Mb each. Now they vary usually around of 100Kb. I suffered CTD few times, however it seems it happens after to often use of a quicksave function. And the great thing is, that this simple line in SKSE.ini file is constantly and subtly active somewhere in the background, like an invisible and patient guardian constantly watching the remaining dirt and not allowing it to overgrow. It also seems to not slow down the game performance. I'd like to thank wholeheartedly to the SKSE creators (did I say Talos bless you?) for this simple and light solution. I also thank you, Flexcreator, despite I did not use your method. Regardless your idea is safe or not, you faced bravely the problem and also initiated a creative discussion, which eventually can lead this serious game issue to be solved. Please, pick the divinity you wish to be blessed by and I'll look for a proper shrine to kneel before. Greetings



Corrupt Saves - StrCount > 0xFFFF - CTD on load


A limitation in Skyrims save file format has been discovered which causes saves to become unloadable - CTD on loading these affected saves. This is NOT random CTD on load that Skyrim does every now and then. These saves will never load.
Just to put it in context: Vanilla Skyrim + Dawnguard + Hearthfires + Dragonborn + Unofficial Legendary Patch + SkyUI + Live Another Life = A total of 28,619 strings. Nearly half of the field (43%) is consumed with an almost vanilla setup and that's a fresh game, sitting in the LAL cell. As far as we can figure, as more and more scripts are instanced as the game is played, more strings are added and strCount grows.

Read about it here:

http://forums.nexusmods.com/index.php?/topic/3924850-corrupt-saves-strcount-0xffff-ctd-on-load/