I had to reinstall macha3 because it stopped working / no contact with the machine /, after that the behavior of the motors and one servo changed, although the values ​​in the tab where you set the parameters of the motors - no, they remained the same. Before this installation, I overwritten / thought this would help /, the <MACH> folder that was long saved with different settings and now everything has changed. Could this overwriting of the <MACH> folder with an older copy contribute to this?
I heard that even after a new installation, MAch remembers some settings.

If I understand what you are asking, If you just changed one of the existing lathe or mill profiles it would probably get written over on a fresh install. If you created a new profile for your machine with a unique name it should still be there and would not be overwritten in the installation process. If that is the case create a new profile before you start to rebuild so it doesn't happen again.