Welcome to Wonderfields! This is the first world I've made and it took a really long time to finish. As far as I've tested it there are no problems, however if you find any major issues please let me know and I'll try to fix it.
The world is partially populated but what I've noticed is that when your first enter the world, the game won't let you choose one of the existing households to play, so you have to enter 'Edit Town' then go back to choose an active household and you'll be able to play one of the families that come with the world.
The second thing I tried to do but was unable, was to import Sim made paintings into the museum, as far as I can tell that is impossible so the museum will load empty frames.
For Wonderfields to run the way it was intended to, you will need all expansions and stuff packs but no Custom Content.