This will popup a dialog asking which directory you normally keep your archives in. After setting this, clicking the home button on the toolbar will show a listing of the archives present in that directory.
This pops up a dialog with two checboxes. If you want files added to archives to be stored from there full path, for instance /bin/sh, check this. Otherwise they will be stored from the directory they are dragged out of in KFM.
The next checkbox should be checked if you wish to only add files to an archive that are new than those present in the archive. This may not work with all archive formats.