I have a diagramView that is set to 100% width. I also have an overview on the page.

I am getting a strange problem that is best described using this image:
http://imageshack.us/photo/my-images/52/jdiagram.png/

Basically, the image is being cropped, even though there is plenty of room for it to be displayed. Is there something I am doing wrong?

One another issue on the same image - the arrows seem to be too big. Is there any way of spacing the diagram out a little more, or reducing the size of the arrows?

Is there any way to get the diagram to expand automatically according to the nodes within it?

Try this:

var bounds = diagram.getBounds();
var deviceBounds = view.docToDevice(bounds);
var viewportWidth = parseFloat(diagramView.style.width);
var viewportHeight = parseFloat(diagramView.style.height);
var scrollX = deviceBounds.width / 2 - viewportWidth / 2;
var scrollY = deviceBounds.height / 2 - viewportHeight / 2;
var point = view.deviceToDoc(script.createPoint(scrollX, scrollY));
view.setScrollX(point.x);
view.setScrollY(point.y); 

The variables view, diagram and script reference the DiagramView, Diagram and ScriptHelper objects respectively. The variable diagramView is the HTML declaration of the DiagramView control on your page. I'm using diagramView to obtain the current viewport size.

Regards,
Meppy