Zumba Fitness Rush

From the main menu, select the Full Class option. Then select "Create Custom Class". Pick any slot and then click on "Create". Add one song and save your playlist. You will need to repeat a second time with a different slot to get Silver.

Doing this 4 times, with 4 different slots, will get you these two as well.

Create Custum class and add as many songs you like. Save it. Repeat.

WARNING! When I created my first playlist, I played the eight songs in it, and got 5 stars on three of them. Afterwards nothing was unlocked (bonus videos) so I checked the single songs menu. None of my progress were tracked.