this is two years late but if anyone has this question in the future, each world's boss requires a certain amount of star power to access (star power is calculated by 1*(stars gotten in current world) + 0.5*(stars gotten in other worlds)).

basically you can do a lot of quick stars in worlds 1 and 2 to avoid slower levels in world 3, and world 4 and 5 stars are faster than having to go through 6-2. idk the exact stars that you need but the current wr should have a good route. i think it beats the game in 84 or 85 stars.

Why are the anonymous numbered?