Beleive me when I say this. I am not trying to be critical. I am trying to help. You can't set your device up that way. You MUST have equal numbers of neutrals in each stack. You are way better off leaving that last stack with only 4 neutrals off completely. What happens is that the voltage will devide equally between the gaps of each stack. If you have 12 volts in your 6 stack parts you will run 2 volts per gap. With the stack that has only 4 neutral plates you will have 2.4 volts per stack. I know it appears that it is working well but it is not. Effeciency tests would prove that. The stack with 2.4 volts per gap is using all the amperage it can gobble up while the other 2 sections are using very little. They are acting like nothing more than a resistor.
As far as alcohol. I am from Alaska so I have lots of experience here. If you run a strong (28%) solution of KOH to water your cell will never freeze. You only need to worry about the bubbler. A solution of 75% distilled water and 25% alcohol will stop the bubbler from freezing. Your issue will be alcohol evaporation. Alcohol evaporates much faster and at much lower temps than water. It will eventually evaporate enough that it freezes up. Then pressure backs up and your cell leaks. As long as you monitor it closely alcohol in the bubbler will work.
Your next problem will be water vapor freezing in the delivery tube. If the tube is not warmed up enough to thae any condensation every time you drive then the tube will freeze shut and block the entire delivery system. Thought I would share some of the issues I had in Alaska to save you some time and trouble.
Larry
2008 Nissan Frontier 4X4 Nismo. 12 MPG baseline with my normal commute and heavy stop and go daily driving. Generator installed and working on 3/29/2009
Up to 14.5 MPG with no enhancers. Still testing the effects of lots of HHO and no electronic enhancers.