Open the doors by flipping the switches to reach the end of the level.

Later levels feature a timeline allowing you to go back in time to undo mistakes, take a different branch, or merge two timelines into one!

Controls:

• Click on a tile to move there
• Click on a switch while adjacent to it to toggle it
• When the timeline is active (levels 3 & 4), click on a node in the timeline to jump to that point in time.
• When the timeline is active, click on merge, then click on a node in the timeline. This should merge your current state on top of the one you clicked on.
• Press Ctrl+Z to go back one step
• Press 'R' to restart the level

Unfortunately I was unable to get an macOS build working, sorry.