On July 11th, Daria, DRM and Hackurl all released a song called Mushihimesama: To Shinjugamori. Two days later, Wiz and JUD followed. The songs were a result of a competition between MSX composers, who challenged each other to arrange difficult songs on PSG. As of now, a Japanese and English website on the competition is available right here. It looks like the competition will continue with more composers and more difficult-to-arrange tunes in the near future.
Relevant link: PSG.MOE