T-ster,
What are you using for fuel in your ZDZ. Have you checked the plug for fouling? I burn Aviation 100LL gas. Although this fuel does tend to foul the plugs quicker, I like the performance of the 100 octane. Additionally, during break-in I try to use AT LEAST 93 octane. The instructions say 91 ~ 93 octane for mine, but the oil fuel mix at 40:1 effectively reduces the octane of the gas and I have noticed some preignition when using 91 oct. for the first gallon. Is the engine popping or just nothing when trying to start. You may also want to check the timing since you have changed ignition systems, they may have different requirements.