I have tried Clonex for two years. I could have as well thrown my money down the drain: literally every plant I propagated using it had both very low radication rates and problems developing health root systems. A complete waste of time and money and has since flown right into the garbage.
Japanese maple can be easily rooted without any rooting compound: the key factors are high temperature and moisture. Covering the cutting with a clear plastic bag and putting it in the hottest part of the house where it will get some indirect sunlight are the best ways to increase rooting chances.
