According to the Armory's archives, Sybil and a weapon arrived at the Armory in 1790, from a town named 'Mystic Falls'. However, in Pilot, the town's founding is noted as 1792. According to Family Ties, however, Mystic Falls was not founded until 1860, meaning that it was impossible for the shipment to arrive from there and be noted as being from 'Mystic Falls'.
The sign at Mystic Falls in Pilot, however, notes the towns founding around the late 1700s, so there is a continuity error where the founding has changed from Pilot and then changed back again.
When Stefan becomes human, all of his compulsion was erased and the compelled's memories returned. However, in Silas' case, the compulsion wasn't erased because he was technically an Immortal, not a Vampire.
Additionally, Alaric's compulsion on Elena should have been undone when he became human thanks to the Travellers' spell around Mystic Falls.