The area is accessed by interacting with the basketball hoop in the Gray Road.
Also, I have a list of small changes in 0.101b:
*The music in Wavy Up was changed (no more weird scratchy sounds)
*The Toy World background is less blurry, as seen here.
*A retro-looking system theme was added
*Some other misc. changes to music and a couple of chipsets.
Amusingly, getting captured by the chaser results in Urotsuki getting trapped in the storefront.