Hi,
The use of labs with elearning has changed over time. These days a lot of virtual labs are being offered. I had the same situation a couple of times and mailed MS about it. The final explanation i got about the last one was that i had to change quit some
setting within windows to get the download proces started. I think that was not the answer i was looking for and told it via mail. I had been dowloading the labs for a long time. After some mail exhange it was clear the the lab had turned int a virtual lab.
You can read about the virtual labs on the micorsoft learning page.
Maurice