I am running Windows 10. I have installed Sims 3 v1.69.43.024017 and all the expansion packs/stuff packs through Origin. The game runs smooth as butter. However. When I try to add custom content, specifically .package type files, they don't show up. Installing from .sims3package files works fine, and I can see that content. But I have done everything that everyone seems to suggest I do and some things I have thought of on my own (downloaded FrameworkSetup.zip & re-added Mods folder from that, etc), tried putting the files in every location I can think of, but .package files just don't show up. I'm so frustrated at this point, the game was working just fine the last I knew, the last time I went to play it (on the same system etc). And I'm doing the exact same things as before. But the .package files just aren't working. Can anyone tell me what might be the problem? Has anyone else run into this?

Play a game, then "Save As" and give it a completely different name.
Now Search for that file and see where the game put it. It seems to have a bad habit of finding folders called "Documents" in other places, like One Drive, and deciding to use that folder instead of the one it's supposed to use.