Yes, I have used those instructions. The extension installs and works correctly.
I am using mBlock v 3.4.10 on windows
The problem is that mBlock is only programmed to copy *.h and *.cpp files to the temp project directory for compiling.
It also needs to copy .S files (assembly language files). As some Arduino libraries include assembly files (.S) for compiling.
The second problem is it doesn't copy sub folders from the extension's folder to the temp folder, again some arduino libraries have include files in sub folders.
Every time you click "Upload to Arduino" or "Edit in IDE" files are copied (by mBlock) from
%appdata%\Roaming\com.makeblock.Scratch3.4.10\Local Store\mBlock\libraries\EXTENSIONNAME\src(*.h & *.cpp)
Can you please add *.s and subfolder copy in the next release.