No. You must deliver a cube to a different city than its origin.
FAQ for one Certain Game
The intent of the designer is that track and ownership markers are not limiting elements to the game; in practice, you may run out of ownership tokens and/or track. You are limited to the track tiles in your set, but expansions and other releases may include additional track; these can be added freely to any game of Steam using the original rules. Alternate markers may be used (additional player pieces, other markers) to denote ownership of track as needed.
Yes. You have “extended” the track to a city, so the track is yours. If another player owned the incomplete link, the link is completed for them.
No. Page 7 is talking about track building in general. Page 9 is referring to town hexes, and is specifically referring to replacing a town hex where one or more players may ALREADY have links. You are required to maintain their tracks when replacing the town tile, but any new track spurs you build are yours. You are not “extending” their track; you are maintaining track they already own.
Purple-bordered waterways are canals. As noted on page 9, these are identical to rivers.
No. This upgrade is free (with the loss of one of your two goods deliveries this turn).
Yes. You may choose, during your build track phase, not to take those actions. (In Base Steam, you must declare immediately when you obtain the action tile whether you are exercising the Pass Option.)
No. You may replace any town on the board with a New City tile, whether you (or any player) has track to it or not.
Usually, no. This action means that you will choose action tiles first during the NEXT turn. However, this tile is also the best tile for the second tiebreaker at the end of the game (page 13).
Yes. As long as each link is extended by at least one track piece each turn, you do not lose ownership of any of your incomplete links.