Quick Inquiry - Opening Library Source Folder from Main Menu

Trying to tweak something in my custom Kodi skin to activate network share folders from the main menu for general folders I put Movie Trailers, cartoons, random videos etc into. Currently I have a menu entry in the Includes_Home.xml with this string that works 

<onclick>ActivateWindow(videos,"smb://KODISERVER/D/Movie Trailers/",return)</onclick>

What I'd like to do is eliminate the smb path direct part and open a folder from the Kodi sources where I have added that same smb folder "Movie Trailers" type set to 'none". I've tried reading the skinning manual for a string that would work and couldn't come up with anything so any tips would be great. I have tried a few things such as below but thus far only opened the main Sources folder.

<onclick>ActivateWindow(Videos,Files/Movie Trailers,return)</onclick>

<onclick>ActivateWindow(Videos,Files,Movie Trailers,return)</onclick>

With this change if I ever change the folder location I only need to update the source location in each Kodi client install and not update the Includes_Home.xml in the skin itself.

Thanks!