Well if you donwload it with netscape...netscape will ungzip the file automaticly but leaves the .gz at the end... use the command 'file Wellenreiter-v09.tar.gz' to find wat format you now have, i bet you will receive gnu tar archive...so rename it to Wellenreiter-v09.tar and use 'tar xvf Wellenreiter-v09.tar' and all should run :-)

greetings

max