FS2_Open is the original FreeSpace 2 engine, released to the open source community by Volition in 2002. Ever since then, a dedicated team has been hard at work keeping the engine up-to-date, enhancing it, fixing the bugs, and porting it to non-Windows platforms.
This is the latest complete Transcend package. Installation instructions included. Requires a 2009 (or later) build of FS Open.