Hi @steviecoaster,
If you want to use the offline installer in a script (which I think is best for a Chocolatey script), then just unzip it after downloading. I know it's an .exe file, but you can just unzip it like any other zip file (e.g. with Expand-Archive or something in PowerShell).
Once you've done that, you can just run the hub.exe per the silent installation instructions.
Alternatively, you can write a script like this, which will instruct hub.exe to download a version:
# create working directories
mkdir C:\InedoHub
cd C:\InedoHub
# download and extract file to working directory
Invoke-WebRequest "https://proget.inedo.com/upack/Products/download/InedoReleases/DesktopHub?contentOnly=zip&latest" -OutFile C:\InedoHub\InedoHub.zip
Expand-Archive -Path InedoHub.zip -DestinationPath C:\InedoHub
# perform silent installation
hub.exe install ProGet:5.2.3 --ConnectionString="Data Source=localhost; Integrated Security=True;"
The only downside to this approach is that it's not really version controlled (i.e. it's always using latest Inedo Hub) and the package can't be realizably internalized, since hub.exe will download files from the internet.
-- Dean