Mazak 1K Laser cutting problem - any help?

I have a Mazak New Turbo X-48 Champion (1,000w) that I have been using successfully for over 5 years. I have been using Hypertherm ProNest v19 for nesting and CAD drawing of the parts I cut, which average 4,000-5,000 parts per month (from 16 ga. mild steel). A[/SIZE][SIZE=13px]lthough I have had various problems with the machine over those years, I have always been able to get it going again. However, I have a new problem that I can't figure out. About a year ago, I had a problem setting the nozzle gap due to a problem with the profiler potentiometer and so I replaced it and the machine worked fine thereafter. Recently I was cutting a sheet and when the sheet was finished, I changed programs to one that I use to cut the sheet skeleton apart so that it is easier to remove from the table. The machine made one cut and lifted to move to the next cut, but when it lowered to make the cut, the head moved too far into the sheet and triggered the auto Emergency Stop function. Reset and tried again….no cigar. At the suggestion of a Mazak tech who has helped me before, I changed the potentiometer…. the nozzle crashed into the sheet and triggered the auto emergency stop again. The tech suggested I change the “gold box’” that is used to fine-tune nozzle gap settings. No change. I also thought it might be a glitch in the program, so I tried several programs I have cut successfully many times before, but the problem still exists. I am at my wits end. Any help out there?