In early 1990, Mindscape had to deliver pre-releases of Captive to magazine publishers in order to advertise it. At that time, the game was still in development and opened for changes. The screenshots provide interesting ideas the programmer initially had that didn't make it in the final product.
The hand buttons were arranged differently with the most obvious change being the two buttons located on the first column. The first button appears to be a person walking through a door, and this suggest a method of leaving the game. The button under is a floppy disk pointing to a map which was probably used to load a game. At that time, the floppy disk button found in the final release could have been used to only save the game and not load it.
The problem with this layout is that the hands and play screen (the droids vision) are separated by these two buttons. If the player had the mouse cursor on the play screen and quickly needed to use the first hand, there was the possibility of hitting the "Quit" button instead (or whatever it was meant to be.) Moving the hand buttons closer to the play screen was a wise choice.
Another interesting object on this screenshot is the image on the left red hand: A floppy disk. Perhaps clipboards didn't exist at that time and this was initially used on computers to unlock laser beam doors or release planet probes. One other possibility is that a floppy disk was the ancestor of the planet probe because the text "Disk has revealed a base" exists in Captive and can only be seen by right-clicking a hand that has a planet probe (make sure to read the bug associated with this text in the Bugs page). Perhaps the player was carrying this floppy disk to be inserted in one of the base's computer in order to copy the next destination. Once done, the disk could've been inserted in the spaceship which would indicate the next base.
Later, the need to orbit and land was required. The "Quit" and "Load" buttons were replaced by "Orbit" and "Land"
In the final product, these functions are replacing the "Turn Left" and "Turn Right" buttons while being in space. Oddly enough, the buttons were also present while being in a base:
It's safe to assume that they weren't doing anything while the game was in that state. They were eventually replaced by the "Pause" and "Zzz" buttons. As for the inventory, the following screenshot has been found:
If you pay close attention, you will notice two uncommon items: An explosion and a fist. The fist can perhaps be a droid part that was later modified to look better, but the explosion cannot be explained. It is also interesting to note that the droid does not have any chip but is yet fully able to function (a droid without a chip does not have the skill to appropriately use parts and most weapons).