Checkpoint 8 (Version 0.9.0)

The early version of Checkpoint 8, known as Brownie can be found in version 0.9.0, but it was unused. It has many differences from the final version.

Stage 1
Stage 1 has many circular obstacles (called gyro) that operate like Spinning Hexagons. Octahedral Crystals and an Explosive Ball are also found here. (Presumably, the gyros developed into the Spinning Hexagons, with only the shape, color and the gradient changing.

Stage 2
Stage 2 contains many Spinning Metal Disks, but with thicker, slimmer glass bars. Star Shaped Crystals, Infinite Balls and Octahedral Crystals also feature here. However, the Pyramidal Crystal is absent. (Many features of this stage are reused in the actual Checkpoint 8, only with Pyramidal Crystals added and thinner, wider glass bars, as well as a color change and gradient change. Also, the Spinning Metal Disks spin quicker than normal, and the ones that shift have 4 glass bars instead of today's 3.)

Stage 3
Stage 3 contains many string obstacles, such as the cube, octahedron, and cuboid on strings. They are all exclusive to this old version of Checkpoint 8, but they were possibly scrapped for thinner, normal-shaped string obstacles (triangle, square, pentagon, hexagon, painting).

At the beginning, there is an Explosive Ball, which also features at the beginning of the actual Checkpoint 8's respective beginning segment of the third stage. However, there are also Infinite Balls that feature in this stage, which are not seen in today's Checkpoint 8 stage 3.

All stages end with two-button doors, like the current Checkpoint 8. However, they are all blank, without Power Ups at the end. Apparently, this stage's music is from the Smash Hit Gameplay Teaser which went unused until version 1.3.0 (when Game Modes were added), and then used in Zen Mode.

Video
The video made by NewBartoszx1 shows the entire early version of Checkpoint 8.