It is not that complicated.
You can just download the whole package here: http://actiongame.svn.sourceforge.net/vi.../?view=tar
If there is a binary update, you can just browse to the binary folder on SVN and get it from there, save it to your harddrive and then overwrite the previously downloaded SVN .exe file in the ac/bin_* directory. Example for windows: Go to http://actiongame.svn.sourceforge.net/vi...e?view=log and click download on the last revision if it's newer than what you have. Then overwrite your ac/bin_win32/ac_client.exe with it.
If more than that is updated it's probably easier to just get the whole package again.
(I know an SVN client is even easier, if you want to install one and take the time to learn it. Everyone can use their browser.)
You can just download the whole package here: http://actiongame.svn.sourceforge.net/vi.../?view=tar
If there is a binary update, you can just browse to the binary folder on SVN and get it from there, save it to your harddrive and then overwrite the previously downloaded SVN .exe file in the ac/bin_* directory. Example for windows: Go to http://actiongame.svn.sourceforge.net/vi...e?view=log and click download on the last revision if it's newer than what you have. Then overwrite your ac/bin_win32/ac_client.exe with it.
If more than that is updated it's probably easier to just get the whole package again.
(I know an SVN client is even easier, if you want to install one and take the time to learn it. Everyone can use their browser.)