We purchased some last year - and while my kids LOVE it, I could live without it! I never added the water like on the commercial, so I can't help you there. Can you maybe layer paper towels on it to soak up the water?
I can tell you that this is now an outside only toy!
since it has something in it to not dry it out, i don't know that that is feasible......my son got it for his bday in january-----we had the long no water, no in your eyes,stays in the big container i got for you, wash your hands afterwards, DO NOT EAT IT, etc. After i read all the warnings/disclaimers, it probably would have been safer to get him a woodcarving set!!!!!!!
I think I remember reading in the directions that you could pour alcohol on it and let it dry that way, but that it will never again resist water the same way. I think that stuff is just awful. Who knew.