It sounds like you are running the win-install.ps1 by double click, akin to a batch file or exe installer.
I find it better (more natural) to invoke the installer from an actual PowerShell (e.g. run PowerShell, get a powershell prompt, navigate to where the ps1 file is, invoke It via .\win-install.ps1
That will leave things open so you can see all of the output and messaging from the script.