That works nicely. :)

I have even added it to SidePane.htm:

<td><moi:CommandButton icon="icons/UnHideIcon.png" onclick="/* Show all except Style=Archive */ var index = -1; var style = moi.geometryDatabase.findStyle( 'Archive' ); if ( style ) index = style.index; var objs = moi.geometryDatabase.getObjects(); for ( var i = 0; i < objs.length; ++i ) { var obj = objs.item(i); if ( obj.hidden && obj.styleIndex != index ) { obj.hidden = false; obj.getSubObjects().setProperty( 'hidden', false ); obj.selected = true; } }">Unhide all<br>except Archive</moi:CommandButton></td>