The source code of the 3DO port was licensed under the GNU GPL in 2002.
SC2 added a large number of species and ship types to the already diverse cast and replaced the first game's strategy-based scenarios with a story-driven space exploration adventure game that included diplomacy with the inhabitants of the galaxy, some resource gathering sub-sections, and instances of the melee combat of the first game whenever diplomacy failed.
The contents of the soundtrack of the PC version were determined by running a contest which anybody could participate in, composing tracks based on a description of the game.
Star Control II was highly influenced, both in story and game design, by the games Starflight and Starflight 2: Trade Routes of the Cloud Nebula, developed by Binary Systems. Indeed Greg Johnson, StarFlight's lead designer, helped write dialog for Star Control II and Paul Reiche III contributed to Star Control II's alien communication system.
David Brin's science fiction series about the Uplift Universe is often mentioned as inspiration for the Star Control II universe, as well as Larry Niven's Known Space universe.