The position of the template is not legal, It cannot be on the Air the impact point. The smoke goes Up but not down. https://infinitythewiki.com/Smoke_Ammunition
so if a trooper throws smoke on the edge and not hanging in the air, in that case how does the smoke area spread? like in the first or second example?
Remember that the base you depict in both examples are just game aids, they're not part of the targeting process. It's probably best to remove them.