I edited lydia using the npc editor 0.75.1
when i launch my game with my mod activated the game starts properly but when i load or continue my game it crashes in the middle of the loading but when launch my game with deactivated the game works fine
i placed my mod in the last of the load order but still the game crashed
i have placed both .bsa and .esp file into my data folder as well as the texture and meshes folders also
I had a similar problem with a mod,
Check the files "plugins" and "loadorder" at this location C:\Users\"Your username"\AppData\Local\Skyrim
Make sure that there is only one "Skyrim.esm" at the top, if there are 2 just delete one and save the file.