I just wanted to share some good news! My „Advanced Glass Material Pack” is now free for everyone! I hope to see some cool projects 
enjoy!
Get the pack on Unreal Engine Marketplace
Source : http://www.michalorzelek.com/blog/advanced-glass-material-pack-is-free/
Hey,
I was looking to use this in my current project but it’s unavailable in unreal even though I have it. Is there a working link where i could get it?
Thank you
I tested here and it is working, the package still exists and it is available.
The Epic Launcher is super slow and it will display “Unavailable” button for a long time, but after some minutes it will change to “Add to Project”, if not just change the Launcher window to Home and then click again on the package again.