I took a pair of sims on a date to the Rattlesnake Juice, they had a great time, then went home. I exit the household and see that there is now an orange triangle over Rattlesnake now. I hover over it and it is labeled "Incomplete." I checked other versions of the lot and they are fine.

I just downloaded the game, did I break part of it already? How can I fix this?

As I recall, the Incomplete label means the venue is not meeting the item requirements for the selected lot type, use Manage Worlds to edit the lot and click on the top left icon on the screen, you should then be able to see which requirements are not met and fix it.

Getting an incomplete lot like that shouldn’t really be possible unless you are modding venues.

I was just about to mark the thread 'solved' as I found it was a mod/patch conflict and popped the prob-mod out and things are working again.