Oh - the guide with the puzzle answers (yeah I not only looked I printed it out - shhhh don't tell)

***SPOILER***






"Puzzle 10 requires Level 3 of both Engineering tech and Exploration Tech. Drag a villager to the ancient covered floor in the southeast part of the village and they will begin uncovering the site."

Puzzle 12 needes Culture Tech lvl 2 for the sewing hut - according to the guide.