I know this is an old post but I just figured this out myself and thought I would reply. With the newer version of Notepad++ make sure to put the dll file in a directory of the same name in the plugins folder. now you should see it in you plugins pulldown menu.
Is there a way to change the look "Style" of the item that is being highlighted per the Track Caret option? Right now it's black with a very light grey background. I would like it to stand out a bit more like maybe a bolder background color.
TabStrip event "Changed" also runs when form is first opened.