Fillbots/Unused

Rhythm Heaven
Fillbots consists of the following versions in Rhythm Heaven:

Early Builds
In the Summit Fall 2008 Build of Rhythm Heaven, this game was known as Robot Factory.

In the E3 2008 Build of Rhythm Heaven, the quote for the OK epilogue seems to be reused from Built to Scale ("Sometimes, being OK is good enough.") rather than having its own ("You did good out there.")

Miscellaneous
Despite technically having three versions in the game's data, they are all identical.

Rhythm Heaven Megamix
Fillbots consists of the following versions in Rhythm Heaven Megamix:

Unused Content
There is an unused Practice theme intended for Fillbots 2.

There is an unused image in Fillbots 2 showing a factory with a strawberry and the number 2. This, alongside the information from Robo Juice, implies the red oil in Fillbots 2 is actually strawberry juice.

The ROBO S model from Fillbots 2 in Rhythm Heaven still exists in Rhythm Heaven Megamix. It's functionality is almost entirely indentical, with the exception of one bug causing the filling sound effect to not play if the player starts pumping a little early. The short version of Fillbots has it appropriately colored purple like the other models, and Honeybee Remix sees it colored yellow, along with being decorated with bee wings and antennae. the The blackout also exists, however it is buggy in appearance:
 * It causes the robots to be recolored black, which unintentionally hides their eyes in the dark, and causes them to turn invisible once fully filled. The robots have unused sprites with a white background around them, which is a leftover from Rhythm Heaven in which this white background was used to hide the excess oil while fueling. The recoloring function of the blackout appears to be intended to hide the white background, however the final game uses a mask to hide the excess oil, making this function completely unnecessary.
 * It causes the pump to be recolored black, rendering it invisible. The pump has a white rectangle to hide the actual pump when it goes above the white square, however in practice this would be all offscreen anyway.
 * The gears added in Rhythm Heaven Megamix are built into the conveyer belt animation, and remain visible during the blackout. This causes the robots to be partially visible as they assemble.