When Ron attempts to blow the door up using his claymore mine, he places it sideways. In the next shot of the mine the sign 'Front toward enemy' faces the characters. Ron would've blown them up.
When Leslie is playing "We Didn't Start the Fire" the office door is open then in the next scene it is closed and Ron unlocks it with his wooden key.
In a flashback scene in January 2015, Leslie confronts Ron about his Morningstar project and says she is upset that the development will require Ann's old house to be torn down. Ron responds that she shouldn't care because Ann hasn't lived there in 5 years. Yet, Ann lived in the house up until some point during her pregnancy when she moved in with Chris, and could only have been gone from it for upwards of two years in January 2015.
During the flashback scenes, Leslie would have been about halfway through her pregnancy (carrying triplets) at April's party and would likely have just given birth shortly before the Morningstar incident. However, neither scene shows Leslie with any signs of pregnancy at all.
When Leslie mentions that she will play (now-called) Terry's song from the Summer Jam 2007 to annoy Ron she incorrectly refers to him as "Jerry". Perhaps this is because he was called Jerry back then, although this would mean that someone acknowledges that Gary/Jerry/Larry/Terry has more than one name.