on Windows, double-click on the file you just downloaded and follow the instructions on the screen. You can choose the language during installation
on Linux, install the Debian or RPM package, or expand the downloaded archive using the following command line: tar -Pxvjf ecmerge.XXX.linux.x86.tbz.
on Solaris, expand the downloaded file using : bunzip2 ecmerge-XXX.solaris.x86.pkg.bz2 then install as root with : pkgadd -d ecmerge-XXX.solaris.x86.pkg.
on Mac OS X, double click the .dmg file which opens as an archive, you can run ECMerge from there or install it by dragging the ECMerge application onto the Applications link included in the .dmg file.
for all the platforms, you can change the language of ECMerge after installation in the Preferences... dialog box.