Finally got 303. There is a trick... or at least a realization that escaped me for the whole game, since nowhere it is said that you can do that. If you are stuck at 280 something, a hint: see the screenshots of the people that got a perfect score. What is missing?
I finally got the board cleared, with 288 points. I hear there's people who get as much as 303. Maybe after some days of rest from this I'll give that a go :).
Great game! Looking forward to checking out other games by Daniel.