Well thanks to Klopirat in this thread we know that a code was in the video from the article: 0N59BHP9ZQ . This unlocked the 3rd tile in the first row, which has an icon of a treasure chest with a play button. The article also states that more codes will be available in future Youtube videos so in conclusion the treasure chests are Youtube videos and there are 3 more tiles to be unlocked.
Next they mention: "Look for our survey in articles on the website during Update 0.11.8. Share your opinion, claim your gift, and unlock a map element. " So I'm going to assume the 4 tiles with document icons are the articles in question.
This also means the timer is when the videos/articles are going to be released and not how much time you have to complete a mission.
That leaves the 5 tiles with crossed swords to most likely be the combat missions which I'm guessing will become available in few hours after the daily reset, perhaps. They're also the only ones without a timer so you can complete them at you own pace.
I could also be wrong but so far that makes sense, at least to me...