I have submitted a request via the Output Style Request form for a new style based on Harvard Referencing, for Henley Business School. The form did not allow me to attach a PDF with the full style guide. The PDF is attached here.
Who creates new styles - is it a Clarivate staff member or a volunteer from the community?
Referencing in the Harvard style LA-AR2_7A_Sep2017.pdf.zip (376 KB)
http://endnote.com/downloads/output-style-request is where you put it to ask Clarivate Anaytics to do it. I have no idea how responsive they are.
You can also ask here, if you are specific about what changes you require and another user might be able to help quicker.
The form has a URL spot, which is where I would have provided the link to the PDF?