Open Safari on the destination box. You want to use Safari because of the integration with the MacOSX allowing easier installation.
Navigate to http://metissian.com/projects/macosx/subversion/.
Select the binary you want. When in doubt, select the newest one. If you have an older Mac, look for the PowerPC compatible Universal binaries.
The DMG will begin downloading. When completed, you may receive a warning message that your downloaded file contains an executable program. This is what you want, so continue.
Selecting the continue will begin the binary (program) installation. If the installation doesn't automatically continue, and only the DMG opens, double click on the SubversionClient icon (an open box) to continue the SVN installation.
This installation will make the svn commands available on the command line, which means you'll need to use the Terminal application (or X11 + xterm, as I prefer) to access the svn commands. Using the Terminal application will open a shell (bash, csh, tcsh, depending on your configuration), which accepts command line input commands. In order for this to be effective, however, your shell needs to know where the svn commands are. And for this, you may need to adjust the PATH variable.
Hi!
You're probably looking for the details of the whole Gallery PostNuke to Drupal conversion (including some of the pain Bharat went through with it). I'll get that written up in the next day or two. If you're a PostNuke person looking to transistion to Drupal, well, yeah, I'll get those details up, too. You can contact me in the mean time, if you have specific Drupal/PostNuke/Gallery questions that I can answer.