1. Yes. When you create a program, there are parameters to use for different settings. One of them is about converting light wavelength to Hz.
When it comes to healing vs killing presets: first thing to keep in mind is that the "what" is much more important than the "how", i.e. frequencies are that do the actual work, the waveform is how those frequencies get delivered.
You can always use healing waveforms both for healing and killing, but for killing, those won't be that efficient.
Also, you can use killing waveforms for something that needs to be healed or entrained (like for instance sending substance-emulating frequencies), but then that delivery method will be too harsh and would probably cause unnecessary Herx-like responses.
So, what it all means is that when in doubt, use a healing waveform.
2. If the cause is a pathogen that should not be present in the body, then kill it.
If the cause is a lack of proper function, then heal it.
If you don't know what the cause is, then use either a "Kill or Heal" or "Heal" Shell Preset to load the programs into.
3. From personal experience, I have found universal H-bomb to be effective at both killing and healing so I use that shell in most of my programs as well as to run by BFB results.
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