Thread:Project:Support desk/SemanticGraph ... download not working properly/reply

That's not a gzipped tarball, it's just a tarball. The program you're using to extract the file is expecting a gzip file, but it's getting a tar file. The program I use had no problem recognizing it as a tar file and opened it properly, but I guess some might not be that smart. Renaming the file to SemanticGraph_0-8-5.tar should do the trick.