Bethesda's release of the Anniversary Edition (patch 1.6+) and subsequent 2023/2024 marketplace updates altered the game's executable code.
This occurs when you try to save changes to an .esp file while referencing another .esp file as a requirement.
: Once downloaded, find the files in your Steam content folder (e.g., ...\Steam\steamapps\content\app_1946180 ) and copy them into your main Skyrim Special Edition game directory, overwriting existing files. Essential Fixes and Setup
Download Creation Kit Fixes from the Nexus Mods site. Extract the files ( winmm.dll , CreationKitFixes.ini , and CreationKitFixes.dll ) directly into your main Skyrim Special Edition folder alongside your newly downgraded CreationKit.exe . 2. Adjusting the CreationKitCustom.ini
The vanilla Creation Kit is notoriously unstable, prone to random crashes, and painfully slow. The modding community has built essential utilities to fix these engine bugs. Creation Kit Platform Extended (CKPE)