Some of these pieces of music are merely loops, or sketches, this is why some of them end so sharphly.
Here is the soundtrack of Waco, a videogame which I worked on as a sound designer and composer. The goal of this casual game is to throw garbage in the right bin (waste sorting). Can you imagine how it is to make a music for that plot? ;) Well, one of the three gameplays looked quieter than the others, so I decided to compose a reggae piece. The principle I followed making this game was to enrich and make the music more complex as the player goes up the levels, so that as you reach the upper level, the density of the music contributes to your greater immersion. On this page, you can listen to this progression on this gameplay.
The music for the two other gameplays stand in the "rock" page.
I enjoyed letting the various elements of this smooth reggae take their time to appear.