You should be able to open the Javascript console in the demo and run the following: JSON.stringify(states)

Copy what's displayed.

Then open the main game and do this in the Javascript console: states = JSON.parse(paste your copied data here)

I actually did have that feature in the game, but I deactivated it once it seemed my apparent save corruption issue was gone (didn't want to bring attention to any possible bugginess). I should reactivate it in an update.