Different spark intensity

So that is frustrating, and it clears a little bit more up. We don't have a manual on this engine as it is not offered here in the USA, but the waste spark ignition does not vary the spark intensity between sparks. However, we just need a blue spark that arcs from the coil boot to a ground.

Again, if the idle is smooth and doesn't feel like you have a misfire then the spark is fine.

The easiest way to tell this is to remove the weak spark boots one at a time from the plug with the engine running and see if the engine starts running rough.

It appears you do this, and you get a change in engine which means it is operating.