Acetone is very hydroscopic, it just loves water, to keep it active you should "soak" your project in a sealed/covered container of some sort especially where the humidity is elevated. I suspect the alcohol is used to remove traces of moisture out of the wood but this a guess at best, simply letting it dry out would accomplish the same thing. There is a very simple test to see if your acetone is wet, will post if anyone is interested. --- John Can.