The new couple in the building, Jane (Christina Moore) and Paul (John Ducey), are in fact married in real life.
During the diner scene, when Jen is complaining about the popcorn, Adam drops his hand in the table and flips his spoon. The spoon lands on his hand and when Adam finishes his line you can see him roll his hand to remove the spoon.
Jeff mentions to Audrey that her story about who stole her yogurt at work is perhaps what put off the new couple in the building. Chastity Ballesteros plays the pretty girl in the subway in the other plot line in this episode. She also starred as Karen in The Big Bang Theory who works with Penny and Penny accuses of stealing her yogurt (S12 E13).