Before they enter the Country store Eric is holding the door open for Roseanne but at the next cut Eric walks in first instead.
When looking at the soap box powder in the store, the name of the soap is "Atomic Suds" but when the box is tilted by the actor you can clearly see the box top reads "Tide".
When Eric takes Roseanne into town in the jeep, she goes into a hospital, and then into the X-ray and Laboratory department - where a single recessed ceiling light is still on, when there hasn't been any electricity anywhere else for months.
Roseanne's hair stays the same length and style despite many months elapsing, and there being no one to cut and style it.
When Michael and Eric are arguing about what to do next after Michael suggests looking for more people and uniting them Eric puts his own name in a statement that was clearly about a feat the Michael had performed.