Setting for power supply....
Regarding the Setting question you asked...
5.) You didn't mention the adjustment figure called "Setting" on the spreadsheet. What this means is that for the cutting heat you have chosen, where on your power supply's settings should this "normal" cutting heat be? In the middle, or closer to the maximum setting?
In other words, if you have a knob to adjust your supply, at what position of the knob do you want your "normal" cutting heat (chosen in the last step) to be? If you are concerned about safety -- put this fairly high, like say 80% or more. By setting this high, you can't dial in much more heat by accident than the usual cutting heat.
Fixed power supplies can't adjust so they should set this at 100% unless there is a specific reason not to.
The Power Supply does not have a single setting 0 -100%. It has 2 dials, one for volts, and one for amps - therefore, would 50% be 7.5v and 7.5a?