It is a shame the developers haven't responded to previous complaint about this. I have to go back to the beginning as did not save properly. The game is too "buggy" with frequent crashes and an awful mechanic where you have to find the correct portal at the beginning to carry on from the last time (if the game has saved properly). It is a shame it is "unplayable because of the bugs " (nor is it updated) because I like it....

How exactly does this puzzle work? I don't get it. Maybe just a little hint. :/ https://ibb.co/qM8mW5n

The current progress has completed the third chapter, and the extra level cannot be passed. I dare not start playing the fourth chapter. The puzzle part is quite good, but the timing of the operation is too demanding. The game is too difficult for me.

bought a key from elsewhere then got removed from steam??

Why does this not work: https://test-steamproxy.haloskins.io/sharedfiles/filedetails/?id=2930866151 Please don't tell me that the red tiles must be configured differently...