Update!
I made the package 4.9 ready, as well as reducing the filesize about 200mb without any detail or information loss!
I also uploaded the file to gumroad, ( UE4 - Luos's Free Rocks & Caves ) its still free but allows people to donate if they want to 
Additional note:
This package is also now permanently embedded in the version available on the marketplace, so if you purchase/update that one, no need to merge it with this one!
Cheers!