I have been for a while checking around and I found the issue I am sure many people have when installing addons. Well, the issue it’s actually when downloading addons and not when installing. Save as sometimes screw things up. So I copied the raw unformatted text and made a new .py file. This time it worked just fine. Sorry for the hassle. I had many other addons which had this same issue.
@animani Glad it worked for you! I thought you were downloading directly from GitHub (that’s how you should be doing it).
Just click the “Clone or Download” button from this page, and unzip the file that you get 
Sure that’s the way I normally do it but when the developers point to a direct .py file I sometimes download it straight away. So this time it was saving an HTML file as .py. Basically, the website page with a .py extension so when I looked inside I saw what was going on.
Hi, great addon !!
Can you make or teach to make an addon for this type of material ???
https://www.youtube.com/watch?v=PnJ3uAG5jYM&t=819s
Thanks!!!
@Zelfor That looks German, but I think I know what you mean…where there is an “up” that is a different “material” than the rest such as when snow is on something or grass like in the demo…That’s just about a material that you apply to the rock object at the end. I don’t think that would be good to include in the add-on itself, but it could be if needed. Do you have any reasons as to why it should be included in the add-on?