Powershell script periodic Server backup and upload to Nexus

I have a windows 2016 server that is being used by multiple teams to process batch jobs. Application files are scatted all over ( some files and folder are in C:\, som are in Programe Files, and some are in Programme files×86. The registry is also being updated by multiple apps. I need a powershell script that will take a good backup of all the relevant files and upload to Nexus. The approach will be to take a backup of files, and registry (gold copy). Then once a week, we will run the powershell script to take a backup, compare with last backup, and if any diff, zip and upload new backup to Nexus. Naming convention for nexus artifact would be release_yymmdd. The script will also include a powershell command to download the latest version from nexus, in case we need to restore a backup or build a new server.