I completed all 16 puzzles, have the GC running around making parties and giving food ... and I still have 3 "mysteries" pending.
#1 is the message "building can be converted" --into what? This is the large building north of the research table. (I have already achieved the puzzle where we now have the "school" and villagers are born with skills.
#2 is "saw something unusual" when I take any random villager to "admire the treasure". I have put the GC on the treasure and he gives "bubbles" indicating something is happening. Does anyone know WHAT is the "saw something unusual"? and
#3 is this "thump, thump" noise that happens periodically --- sounds like the boulder moving but I have already had the boulder removed from the cave.

Any info is appreciated. This game is making me crazy ~~~

the thump thump noise is the villagers exercising! they pick up a boulder and put it down again near the rare rose.
the something unusual is just that at present - orat least I think so!!

#1 - that is puzzle #4. That is a bug that was fixed in version 1.01.

#2, only the villagers know (or do they???)

#3 was answered by Biddysaurus.

"Saw something unusual" is a residual text element, the same as "this building could be converted." I first found the treasure when I clicked on an unskilled person. His action saw "sees something unusual" and I followed him to the beach. I figured that must be where the treasure is and sent people there to dig.

Apparently the message won't dissappear, muh like the one regarding the school.