Lags & Invisible, Frozen & Stuck Sims --> Post here if you have the issue.

@herself_theelf: Don't jump on me but you might want to look into getting some extra RAM and a 64 Bit OS. 2 GB is a little low with all the EPs

It probably won't help with invisible Sims but it might help with the lags depending if they are coming from the spawned cars and stuck sims or because of the low RAM.