Sorry to hear that, I'm sure you'll get used to the E-5 soon
Hmm.... How do I explain... When your shutter speed is not fast enough, it still captures ambient light, so though the flash has "imprinted" the subject onto the sensor, the shutter has yet to close thus ambient light is still falling on the sensor thus creating the ghost, depending on whether its normal sync or rear sync, the ghost will appear in front or behind the subject
An example would be a car, its like, when the car is moving like 200km/h (its just an example), and you need to brake, the time it takes to step on the brake takes less than a sec, that's like our flash, but just because our brake is immediately engaged, doesn't mean the car will stop then and there, it will skid, when it skids, its like our ghost, doesn't really makes sense, but that's the best explanation I can come out with at the moment
Normally when you use flash and the subject isn't moving like taking a portrait, the subject will be pin sharp, but since this is moving, if your flash duration isn't short enough as well, the subject will not be short
Found a video I've watched before, this is as close as I can find regarding what I was saying, check out first and rear curtain sync nearing to the back, happens with slow shutter, hopefully this will help you understand what I meant