Have you got this fixed? Curious as to what you're running. Sometimes there is a known issue with the kit that someone here could suggest an easy or at least a known fix for this.cleaning that carb is a good next step for sure though!
Have you verified that your plug is good and that your igniter is FULLY charged up? Is the idle gap on your carb set to 1mm? When you cleaned the carb, did you pull the needles out completely? Have you verified that the o rings are in good shape? Replacing them is easy and cheap. It's good in these cases to just replace them and KNOW they are good. Be sure to use a good lube when you replace them! Also verify that the carb is good and snug. (that the clamping screw underneath is snug)
Just a few more ideas, things to check...