Is there any way to save a game in progress? Lack of a manual with this one is seriously hindering my and my kids understanding of what we're doing here....

You can find the manual here (although not for masterpiece edition) - http://www.mocagh.org/miscgame/manhole-manual.pdf

And from this very manual - "Remember this is not a race, and you don't win or lose. The idea behind The Manhole is exploration. Take your time, look around, click on everything, and enjoy the journey. Every time you play, you'll probably find something new."

Yes, there is no saving. ;)