Why not tell the rest of the story like you did in your own forum?
"Why is it free? Our modeller, not understanding the need to share his source model files with the team refused to allow anyone access to the source files essentially holding the files hostage. Seeing this as a malicious act he was then denied access to the project and removed from the team. Since his leaving he has now threatened to release the Air Tractor on his own behalf if he doesn't receive payment for the work he has done so far. After contacting several developers to help complete the project it became apparent that no one wanted to use the outdated GMAX program and we would have to start from scratch using 3D Studio Max.
Having to start from scratch means that the ex-modeller would not be getting paid and with the threat of having a free version released when our new payware version comes out, I felt the need to release this myself and let folx mess about with it while our new and fully functioning payware version is being made."