-After the SEGA logo, a demo immediately starts. The demo is really short (the player dies almost straight away) and there is no music, just sound effects.

-The game is called "Motherbase". The European version would eventually use this title, but the American version would be re-named. By setting your emulator's region to Japanese, the title will be changed to "Parasquad" and the title screen will be different.

-The sequence showing how to hack ships doesn't seem to be in this build.

-This proto slows down a lot, and whilst the final version is still bad, this build is far worse.

-The intro to the first level is different, and is missing the very start with the alarms going off. Different ships fly past as the intro continues.

-Enemy placement is vastly different, with there being a lot less things to shoot than in the final version.

-More enemies have been added.

-The hacking demo sequence has been added.

-The first level intro has been updated, but still isn't quite the same as in the final version.

-There are also prototypes available for the 23 and 27th of February, and the 3rd, 6th, 10th, 15th and 31st of March. These need to be further looked into for details on the differences, but the March 2nd proto has the option changed to "options" at the main menu, whilst the March 31st proto has the title changed to "Zaxxon's Motherbase 2000".