my trick for nicEdit, in the situation when no text is selected, is to paste the title given via the Add Link form into the document and select it, then the rest code works as it works when a text is selected.
I used the function pasteHtmlAtCaret described in the following link to paste the title
Insert html at caret in a contenteditable div
this.removePane();
var url = this.inputs.href.value;
var selected = getSelected();
var B= 'javascript:nicTemp()';
if (selected == '')
{
var B = url;
pasteHtmlAtCaret(this.inputs['title'].value || url,true);
}
if(!this.ln){
this.inputs.title.value;this.ne.nicCommand("createlink",B);
this.ln=this.findElm("A","href",B)
}
the getSelected is also a simple function as below
function getSelected()
{
if (document.selection)
return document.selection.createRange().text;
else
return window.getSelection();
}