Installing custom worlds without all expansions?

[snotbubble25]

I want to download some custom worlds, like Angel City, but when I try to install it, it won't let me. My game is up to date with the latest patch, so I'm wondering whether it's because I don't have all of the expansion packs? For some reason, most good custom worlds need every expansion pack, but I assumed that content from a missing pack would just be left out. I have the important ones (or so I thought):

Late Night
Seasons
Generations
Ambitions
Island Paradise
University Life

Can anyone help me out? I really want custom worlds.

[MrsFlynn]

I am not real familiar with installing custom worlds, so you may need to go back to the site you downloaded it from and ask there. They maybe able to help troubleshoot why it's not installing.

I did find this link on installing custom worlds, just in case it helps.

Installing Custom Worlds - Sims 3
http://www.carls-sims-4-guide.com/forum/index.php?topic=26195.msg437912#msg437912