We use multipart Rar or zip files to be able to make smaller individual downloads. We try to keep each files less than 1gb and we use enterprise secure 3rd party servers. Sometimes downloads will be slow or stall depending on many factors like time of day, location and local connection so please try downloading one file at a time and if any file fails to download try again. Use download managers if it helps like in Chrome. Also, try using a different web browsers if you have issues with any button, graphics, link etc. as sometimes the website is not 100% compatible with specific browser/OS/system combinations.
We also added Pulse Downloader application for some of our libraries for easier and secure downloads. Each product will mention if its a Pulse Downloader app. Pulsedownloader is a separate company (we just share the pulse in the name) and you register there for an account and then use our email. Some of our prodcuts will be downloadable via your accounts page. For larger products you will get an email with a code to download via pulsedownloader.