Thank you Phaedrux for the reply.
Going back to the Heightmap, and the example of + value.
The 0 reference, is the height the compensation is trying to maintain to print. IF it s positive then the compensation will lower the hotend the amount it has been save at that XY position in a radius i guess half the size between each point. Correct?
For my last question, Yeah i meant G29. But seeing the involve code to automate the calibration of Bltouch. It would take some coding effort to do the same for the G29 command. I'll put that to rest for now.