Sims not doing it for themselves

How high is the free will set too ? Do your own Sim do stuff on their own if you leave them be ?

Free will is set to the maximum. Sims on the active household will eventually take care of their own needs once they become critical.

Could you try a new game for testing purposes to see if you have the same issue ?

On PCs this can sometimes be accounted to lower end computers but I can't tell how good your mac is (no clue about them)

Are you using any mods or custom content in your game ?

Thanks much for the response. 🙂

I started a new game:

Throwing a party went OK — most guests didn't eat, but they left happy, and those that stayed ate eventually without complaining of hunger or lack of sleep.

Attending a party didn't go as well — some guests complained of hunger long before they ate the food that was sitting there, then complained of lack of sleep. The hosts retired to bed before they finally thanked everyone for attending.

Job promotion didn't go well at all — I got the one of the Wolf family primed for promotion with a maxed performance bar and mood meter; he was on his way to work when I switched to another household for a day to see if he moved up. He didn't.

No mods or other downloads except for items bought from the Sims store. New computer (a Mac from late 2012).

Did they do anything at all or just stand around ? 

The guests at the party my household threw interacted with people on their own.

The guests at the party I attended were mostly watching someone perform with a guitar; the hosts might have been talking to guests or each other before they retired to bed.

The unpromoted Wolf family member presumably made it to work (he didn't have a Missed Work negative moodlet), but remains unpromoted.

I probably should kept track of what the Wolf family's funds were before and after I switched to another house, because it's hard to know if Sims I'm not actively playing are getting out of the house when they're supposed to.

In my own game, "Stephanie", the one adult female in a family I created but don't actively play, has been at level 2 with a full performance bar for a very long time; the teen girls living there are halfway to young adulthood now. When my active household runs into Stephanie, she's in her work clothes, even though I put her in her normal clothes every time I switch to her house to check in on it.

Ayden Van Gould for some reason moved into that house; he has a job, but had the Stir Crazy negative moodlet when I found him, so presumably doesn't get out. Meanwhile, I've run into the daughter from that family outside in the Graveyard; she obviously gets out, but was standing around the Graveyard pointing at her mouth with the starving moodlet before she finally left.

I wonder if it's connected to this issue: http://forum.thesims3.com/jforum/posts/list/661298.page

That is for room mates but might be connected. I don't know if the guru still monitors that thread but it might be worth posting there (make sure to set your language to US)

Thanks. Just posted there, though, as you say, that thread is from a while ago. And for University. And for Sims that are dying. (Mine aren't dying, but just hover indefinately in death's antechamber.)