I couldn't figure out how to get out of the first location. I think I tried all the combinations of mirror colors and movement available.
Viewing post in Cogitatio jam comments
Set the mirror on the platform with the blue gem to blue and set the mirror on the platform with the red gem to red. Then left-click on the first/green mirror and then on the mirror that is now blue. Then click Space. If you walk to the right for a while you should go into the blue mirror and at the same time come into the red mirror (because the red mirror clones the blue one). Lastly, you should be able to walk out of the red mirror and walk into the red gem.