These menu entries allow you to manually build tree segments. This can be particularly handy to investigate what files might exist or to directly build a tree which matches a known server configuration.
In general the Insert command will allow you to insert a new directory or file under the currently selected segment. The Delete command will remove the currently selected segment and all of the directories and files under that branch of the tree.
You may find it easier to utilize the URL Capture Bar to build tree branches than Insert.
There are a few restrictions on where a directory or file may be inserted :
Inserted segments will have a Pre-Text value of "New" with no fusk data or Post-Text. When created the segment editor will be popped up for you to provide the specific information about the new segment, including any Fusk data.
You may not delete the root node of a fusker collection.
Delete can be particularly useful if you accidently add a reference to a web page rather than an image or for tailoring fusker collections you have downloaded from other sources to contain only the content which interests you. After a Directed Search there are often miscellaneous directories and images which were found but don't really interest you and can be removed using the Delete menu option.
Inserting or Deleting a segment does not make use of any user configurations.