Earlier today ingame, I enquired about why I couldn't complete Waiting Quests if I had fulfilled the requirements. I was told as long as two Daily Quests existed, I couldn't receive Waiting-rewards:
Since then I've completed one Daily and one Waiting, but it seems the "Pavement" Waiting Quest still won't clear. I can only assume it is a bug with the game, as I am only 10% my maximum storage capacity for stones, and harvested materials seem unfazed...
My current stone ratio is 182 and rising; still no reward.