Dave,
It might have helped if you said what engine was fitted and someone might be familiar with it, up to now, no clues on its type, even a photo of it might help.
If you have put power to the coil, assume 12 volts, are you sure the coil was a 12v one? I am assuming the power for ignition comes from the flywheel, like the old flywheel mags on 2-stroke motorcycles, mowers etc. You also mentioned a module, this might have suffered by connecting a battery to it, not only voltage but polarity could affect the module.
If we knew more about this engine, it might be easier to diagnose.
Richard