Let me explain my situation : For some reason recently i've been experiencing bad lag-like stuttering and CTD's in my game. I thought this was because i had installed ENB enhanced motion picture, which reduces performance. To fix this i got rid of ENB and tried playing, but the issue was still there. So i threw out my entire skyrim folder and copy-pasted in my backup, only to find that i still experience lag and CTD's. So i figured "Ok, my skyrim folder must be corrupted" and wired over my laptop's skyrim folder over the windows 7 home network. My laptop has not been updated with the latest patch or any of my mod shenanigans, so i figured it would be pure. I brought it over and let steam validate the files/download the latest patch, and now i want to do the shadow tweaks and stuff that were in my prefs file. From your post i'm assuming just a copy-paste would be a bad idea. Also do you know of any mods that would cause the issues i was describing? I don't really run any HD mods.