In some situations, your Nuxeo Platform doesn't have access to internet. For deploying your Studio customization, you need to install the JAR in the correct place on the Nuxeo Platform folder layout and restart your server. See details below.
Click on your project's name and then on the Download Package item.
A snapshot package of your project is generated as a ZIP file.
To download a specific version of the Studio project, go to Source Control > Releases and Tags, select the version you want and click on Download.
Download the ZIP.
Install the Studio package:
Using the nuxeoctl mp-install command and provide the path to the ZIP as the package name
From the Admin > Update Center > Local Packages, using the Upload a Package button.