Glass Road

Production wheels may only be rotated when both brown sectors are empty, and if they are empty the wheel must be rotated (you may not rotate them at other times); you also may not rotate a wheel in the middle of a transaction and multiple rotations triggered in a row count as one uninterrupted process (see p.8).

If you are the only player to resolve that Specialist you may use both abilities in any order; but if another player also plays that same card from their hand when it is revealed, all involved players may use only one of the two abilities (see p.6).

No — upgrade tiles (those with the brick pattern) must be placed on top of the indicated Start building and may not be placed on empty Landscape spaces; ordinary (non-upgrade) buildings must be placed on an empty Landscape space (see p.9).

Immediate buildings must have their one-time effect carried out immediately after building, and once resolved they have no further use for the rest of the game (with the noted exception of the Tavern) (see p.17).

Yes — Processing buildings grant trades you may perform at any time (even repeatedly), but each individual trade is an action and may cause Production wheel rotations (see p.8); also if you build a Processing building you may use it immediately after building (see p.14).