Can't help with the Z issue, but the best way to install a new version of Mach4 and NOT lose your settings is:
Rename the Mach4Hobby directory to something memorable.
Install the newest version from scratch, it will create a new Mach4Hobby directory.
Now go to your old directory, the one with the memorable name, and copy over your Profile, Screenset, any macros, anything else that's peculiar to your old setup over to the new directory.
Wallah, set to go with the new version.
I've done it dozens of times, works like a charm always, and...........you can revert by simply renaming directories if you need/want to. You might also consider making a backup of the entire Mach4Hobby directory to another hard drive or network location once in a while, like before updating to development versions or anything you might consider "risky". Belt and suspenders, don't you know!!!
Tom