If you accidentally overwrite Settings.ini , your paths will break. To avoid this, after extracting the files (and preserving your old Settings.ini ), open the new Settings.ini that came with the upgrade (or check the HyperHQ.exe defaults).
Create a temp folder on your desktop named HS_151_Upgrade . Extract the downloaded archive here. You should see a folder structure like this: hyperspin 151 upgrade files only install