No, Midas Machine has not been cancelled. But its sub-forum overstayed its welcome and has been retired in favor for smaller threads whenever we need them.
When the Midas Machine project started, it was a big, multi-member community project. But over time, people dropped out and the number of people actively working on it shrank down to 2: Chaoxys and me.
More than half of the topics in here are relics of the past, and the only relatively active ones are the engine topic and the graphics topic. And this separation is no longer necessary, at least no more than of any other fangame project on MFGG. Therefore Midas Machine's development will live on as a single topic in Development Showcase, and another one in the Graphics & Audio topic for the music, which is actually the most community driven aspect of the whole project.
On top of this, Chaoxys might still update a graphics topic (or just move this one into Graphics & Audio) in which he posts the stuff he makes and greatly appreciates C+C.
With that said, without you, the community, Midas Machine would never even have started, so thank you for that! And if you are a musician, what are you waiting for? Find Chaoxys and ask him what we still need
-Guinea