I am unable to download the Library when I initially opening Logos 8. I can't find a download button.
Welcome [:D]
Logos Help Center (LHC) has article => Select Which Library Resources to Download with Download Resources section
Keep Smiling [:)]
You are using Logos on Mac or PC? The entire library generally downloads upon installation and remains up to date as long as you are connected to the internet.
If you opted for an install that left some items in the cloud, these items will be downloaded as you have need of them, but they will still appear in the Library pane. If you want to force a download, you can right click on the book tile in the Library pane and select Download.
If that is unclear or if we misunderstood your request, let us know.