When Morvern drags Lanna out of the hotel room and into the cab with the loud music and the decorated dashboard, the shots of the driver show that the dials on the dashboard of the car are not operating, suggesting that the car is, in fact, being towed for filming purposes.
When Morvern changes the name on the manuscript, there is a shot of her hitting the "delete" key repeatedly, followed by a shot of the cursor at the end of her boyfriend's name, and the characters disappearing one by one from the end. In English versions of Windows (and Mac OS X), the "delete" key deletes characters after the cursor, not before it. Depending on the program and keyboard, "delete" could work like "backspace."
The shot of the railway station at the end of the film shows tracks with a third live rail. Although never mentioned by name, Morvern lives in Oban, where the railway station is served only by diesel-powered trains - in fact, no railway lines in Scotland use a third live rail as a power source.