Game files in a .zip archive, download, extract and run Sector Six Windows Demo 0.9.1.exe to play. Report issues in the comments.
This is demo version! Get full version from Steam.
Demo version limitations:
3 story missions. (7 in full version, more will be added)
10 level cap. (unlimited in full version)
No boss missions.
No modular difficulty system.
No secure regions.
No gauntlet missions.
No time siege missions.
No part sets.