The issue is gone, thanks!

Attached are a few of the error logs I got re: the NPCs. Here is the save those errors are from, though my festival stuff is spawning just fine.

I encountered a new bug after installing Seasons. Tested with just Awesome & the config (no store content, no hairs, etc) and the bug shows up in both new and old saves. I've also checked to confirm that I'm using the 11/05/2012 7:54 am version of the mod.

NPCs and ghosts cannot be interacted with. The ghost just stays stuck by their graves and NPCs arrive in their cars and then stand uselessly beside them until I force a reset, though sometimes the pizza delivery NPC takes my sims' money and leaves without handing over the pizza. I've tried to have my sims fire/dismiss/chat with the maid but the action always gets cancelled.

This bug doesn't appear in a modless game.