Basic ignition

I know nothing about alcohol engines, except that they need a lot more compression than gas engines, and they need plenty of amps to run the ignition.
This is where I think the CDI might fail you. The multi-spark feature drops out around 3000 rpm,and then you will be running same as or similar to, any other kettering ignition.
Ima thinking your mag needs checking out, and if fully functioning,you might try a new starting technique, as mentioned above. I see guys squirting fuel down the carb all the time.