Klaus' bowl appears to switch positions when Francine enters the room. It's closer to Roger's tablet before she enters and near the middle of the table after she enters.
Steve's train appears out of nowhere when he squirts Stan with his water gun.
The front door is open the entire time the dominoes exit and reenter the house but once the power goes out, the door is closed.
It could be explained that Roger or Francine closed it but that are still in the kitchen when the power goes out.
Also, the dominoes are all gone when we see the power go out inside the Smith house.
Steve's Train, is actually the PBS character, Thomas the Tank Engine.
Steve's call of "To Forever & Above" is a homage to Pixar's Toy Story & Buzz Lightyear's slogan, "To Infinity & Beyond"
In Roger's garage, although hard to see, he has the Batmobile from the Batman TV series.
Stan & Klaus watch the ABC talk show, Jimmy Kimmel Live
The German song from WWII, Lili Marleen, is heard when Francine is seen waxing her skies.
Steve rallies his 'troops' dressed as an X-Wing Fighter Pilot from the Star Wars series.
Stan getting hit with multiple paint cans on strings is itself an allusion to the movie Home Alone, but upon the paint cans sit characters from Jim Henson's Muppets.
Those being from top to bottom, left to right, Animal, Fozie Bear, Miss Piggy, Gonzo & Kermit the Frog
The Muppets show up later along with a character that is reminiscent of a Transformer & Spider-Man(obviously colored green to avoid copyright issues)
While Steve is rallying the toys, the toy on the far left appears to be an allusion to the Buck Rogers character, Twikki. The blond muscle man is supposed to be the toy, Stretch Armstrong and next to him is supposed to be SpongeBob SquarePants and next to him is a toy that's supposed to resemble a Shogun Warrior.
After the battle w/ Stan, the toy that's supposed to resemble Stretch Armstrong, talks to a toy knight and a big piggy bank that's an allusion to the Pixar Toy Story character, Ham.
The Delorean seen in Roger's garage is none other than the one Stan built from scratch in Season Four's Delorean Story-an
Pedro saying Bye have a beautiful time, is the same thing the security guard says at the end of the episode after the closing credits.
Two of the toys seen in Steve's room are the same two characters that Stan saw while he was getting his vasectomy in Season Two's Iced, Iced Babies