I've had this freezing issue multiple times, though these all happened after the game update on Thursday; it happened at the first two parties I attended after the update as well as at the party I attended today. I noticed the issue today when I was attempting to select a sim as a target for a party action and it froze when I tried to click OK. Eventually, I noticed when I reentered the party that some of the sims were frozen (not always the same ones) and that if I didn't select any of these sims that the game wouldn't freeze on me (I can even select and unselect the frozen sim on the party action menu, I just can't click OK with a frozen sim). That being said, whenever I left this party, the game froze on the logo screen (though when I force closed it and reopened it and returned to the party the progress was saved). Also, if I stayed at the party too long, the party would also freeze (I suspect based on the timing that this may be related to the game trying to make a problematic sim appear). To my knowledge, this party wasn't close to reaching full status at the time I joined.
As best as I can tell, all the issues with freezing are a separate issue from the Invalid Party error bug; I have experienced this issue at parties that have not yet been rendered invalid and in fact the current party I'm experiencing this freezing issue with is still ongoing and was brought to level 10 after I had experienced this freezing issue.
