Dominion: Adventures

The Duration does its future effect at the time printed on the card (usually at the start of your next turn); the card stays in play and is not discarded during Clean-up until the last turn it does something. (p. 5)

You may exchange a Traveller only when it is discarded from play (i.e., after you played it and it is discarded); the exchanged-for card is taken from its pile and put into your discard pile, and the exchange is optional and requires an available copy. (pp. 5–6)

No — calling a Reserve card moves it into play at the stated time but is not playing an Action and does not reduce how many Actions you may play that turn; however, playing the Reserve card initially (to put it on the mat) is an Action and does use your Actions. (p. 5)

No — Events are not Kingdom cards and are not taken into your deck; you pay the cost, do the Event's effect, and the Event just stays on the table (you do not gain it). Buying an Event uses a Buy and you cannot play additional Treasures afterwards. (p. 5)

You must play any Treasures you wish to use during your Buy phase before you buy anything; you may not play Treasures after buying a card or an Event that turn. Treasures with special text are played during the Buy phase like normal Treasures. (p. 7)

Cards on Tavern mats are not in play (unless they are called into play that turn), but cards on Tavern mats are still included in your deck when scoring at the end of the game. (p. 5)