Nemesis is designed to work with multiple games (Skyrim LE, Skyrim SE, and Fallout 4). If it detects the wrong game version, it will look for the wrong engine files, resulting in Error 6006.
No major official article exists, but you will find detailed fixes in: Nemesis is designed to work with multiple games
If you are still stuck after trying everything, visit the Nemesis support thread on Nexus Mods or Discord. Provide your error log (found in Nemesis_Engine/logs/ ), and the community will help. But in 9 out of 10 cases, the manual engine replacement method described above will get you back to generating behavior files without a single Error 6006. check these settings:
If the update fails or crashes at 0-5%, check these settings: Nemesis is designed to work with multiple games