When Alan is shaving in the bathroom, the pattern and amount of shaving cream on his face changes between shots.
The costumes that Evelyn brings in the paper bags for Alan, Charlie and Jake to wear are way too large and bulky to fit in the 2 small bags that she brings.
Charlie says he and Isabella are to have a child together named "Giglamesh". Gilgamesh (not "Giglamesh"), being a mythical Sumerian king from around 2700 BC, would fit the plot and if so, Charlie mispronounces the name for some reason.
As Evelyn exits behind the boys and closes the front door, her dress is caught and can be seen in the closed door.