qtdragon - new tool length after a manual tool change

Is the info in this thread still relevant to QtDragon shipped with 2.9.7? I have a 3-axis cnc router with a manual change spindle and I'm looking to automate bit offset/height setting with a tool setter input on my 7i96s.

Most info will still work. The problem is that there is not really consensus about what automatic toolbit offset en height settings must do.
I had mine working for a while. I switched to 3d printing and will pick up later this spring.