Hello!
As you may know, you get the leaderboard using this function:
LeaderboardCreator.GetLeaderboard(string publicKey, Action<Entry[]> callback);
Well, it has another overload:
LeaderboardCreator.GetLeaderboard(string publicKey, LeaderboardSearchQuery searchQuery, Action<Entry[]> callback);
In place of the "searchQuery", you would put:
LeaderboardSearchQuery.ByTimePeriod(TimePeriodType.Today)
That is how you can filter the leaderboard to display daily entries.