I saved with HTTrack the builders lessons from the website, so that they can easily be downloaded and used, literally as on the website, on any PC, even if the website is down, unreachable, or if one has no access to the Internet for any reason.
I uploaded them on Google drive and on a pair of mirrors:
https://drive.google.com/file/d/0B3YWts ... sp=sharing
https://yadi.sk/d/_9CAXSnP3JVfey
https://cloud.mail.ru/public/FJ3j/nS33LDhrR