There are currently some shortcomings to handle this. We have added an overload
TMSFNCPDFLib1.Graphics.AddGoTo('', 1, '', RectF(10, 400, 100, 500));
Adds a rectangle without text, navigating to page 2 (index = 1). If you want to control zooming, we have added an options parameter:
TMSFNCPDFLib1.Graphics.AddGoTo('', 1, '/Fit', RectF(10, 400, 100, 500));
Next version of TMS FNC Core will address this.
[page /Fit] Display the page designated by page, with its contents magnified just enough
to fit the entire page within the window both horizontally and vertically. If
the required horizontal and vertical magnification factors are different, use
the smaller of the two, centering the page within the window in the other
dimension.
For a complete list of options, I refer to this this document, page 582 (table 8.2)