The game (executable and content) is freely redistributable. That's the archive. Source is not. Both remain proprietary and the copyright holder
has been completely silent about the source says " sources are not available". 24 people from around the web participated in making the game, so it is possible one of them has it (and may not even realize it). But, I think the copyright holder already attempted to get the source from other team members.
If there's any source in the files, it would require forensic methods to find it and it would be just snippets. The source for the memory extender/cross compiler (MOSS) is available (fully GPL). Between the Linux version, DOS version, and MOSS source code, there's some things to be learned.
G++ 2.7.2 to 3.3.6 (I think 2.7.2 was used for the final)
BinUtils 2.6 to 2.19 (I think 2.6 was used for the final)
libc5
MOSS is derived from an early version of the Flux OS toolkit
The final DOS game was cross compiled from GNU/Linux but earlier versions were cross compiled on FreeBSD (I think the team found the GNU/Linux community to be fare more helpful)
Everything is almost entirely C code. Less than 1% C++.
Everything about the Linux executable suggests ELF. Oddly, it produces an error log file titled "a.out" which is recognized as and executable (but isn't, the a.out file is also tagged as an ELF. a.out _is_ an ancient executable file format that was replaced by ELF)
The DOS game is a monolithic EXE containing the entire game (17MB). The Linux version is 300 files with the executable separate from all the content file (9.6MB, take that DOS!)
The itf files of the Linux version seem to be a good place to start for reverse engineering the game. Actually, it looks modable by altering the itfs! But, as I havn't succeeded in running the game yet, I can't test this.
This is just a bit of good news for the open-iw project
https://github.com/TambourineReindeer/open-iw.