Only the Caretaker can take Golems from the map.
Golems fill resource slots and can be discarded, rearranged, and spent for actions like resources. (See the Golem Actions card for details.)
They have Sleeping and Awake sides. Its Awake side is public if a player holds it. (Players' Golems flip to Awake in Crises.)
When a Golem is spent or discarded, flip it to Sleeping and place it in a Rival's empty resource slot. If there are none, you keep it.
In Act II/III setup, Golems flip to Awake.
Act: 1
A: Not in Act I. If the Caretaker continues to Act II, Knowledge Set Free allows for Golem trading.
A: If the player with the Golem Hearth uses a Golem and nobody else has slots. As long as the Golem Hearth is in the game, its holder will always have slots for Golems.
A: Nope!
A: Nope! The text 'can be spent for actions like resources' just means that you spend them in your Prelude to take their listed actions like you do with resources. You can't spend them to take New Actions or, for example, or as inputs for Loyal cards like Loyal Engineers.