http://www.machsupport.com/forum/index. ... #msg131346
There's his new version of the plugin.
And yes, I had the same issue. It was basically ghosting another image. I believe you probably have your steps per inch configured incorrectly, or some other problem related to your x-axis.
I followed the guide in his instructions, set the kernel speed to 25k, upped the steps per inch to 4,000, slowed the x-axis travel in the plugin down to 100ipm, and made sure I had the x and y dpi settings line up. The new version of the plugin calculates the dpi settings for you. Try following the guide in that thread, and that should help.
I'm fairly certain that's all I did to make it work. If you look in the original thread under the impact engraving thing, there's some troubleshooting advice in there as well.
Here's his document : http://www.cooperman.talktalk.net/Engraving.pdf