I've been archiving unlisted Steam demos as I come across them, and I have recently found that the demo for SIGNALIS is... well, nowhere to be found! There's a few people who might have it, but there's no guarantees.
Check your Steam library! If you still have the demo downloaded, great! Please send me the clean Steam files. If you don't, then please spread this post! It would be amazing if we could archive this demo, as it apparently has a few big changes from the release version.