Dave-
If you and yours have not done so already, check out the forums on sawmillcreek.org. Their Laser Engraving General Topics may be a good source of information- methods, equipment, materials and problem solving.
We have a Trotec and most likely could not be convinced to use another brand. My first machine was an Epilog (20 years ago plus) and it still runs in a former employee's basement.