Mario vs. Donkey Kong: Tipping Stars Infinite and quick stars
Start the game and go to Community. Select the level(s) you want to play. After playing as many levels as desired and earning stars, completely turn off the system. You may also be able to exit out of the game and restart it from the home menu. Then, restart the system and game, and go to Community. All of the levels you have played will no longer have the green check mark on them, allowing you to earn stars on those levels again. Repeat this as many times as desired. This exploit allows you to quickly get all of the Shimmering Gold Palace workshop parts (cost 8,000 total stars), including the gold Mini Mario, SGP theme, and the gold pipes and girders.
Bonus levels
Collect four gold trophies to unlock the bonus levels.