button bar icons for inserting children & siblings
 

Are my eyes failing me or is there no longer any kind of a insert sibling or insert child icon in the customize menu ? I note that one of each is provided in the "Tree" button bar, but there are none others to be found anywhere -- not even in the customize menu options.

I would like to have both of those buttons also in a custom toolbar -- how can I have them both places?

Many thanks

Those buttons are only available on the Tree toolbar. You could customize the Tree toolbar to be your custom toolbar. The Insert Child/Sibling toolbars may be another option.
http://www.kinook.com/UR/Manual/inserttoolbar.htm