Having been fiddling this afternoon, it seems the vertical alignment is fixed in latest (20.2) which I can get around by positioning the element better and not relying on the vertical alignment setting, but the main issue...
The barcode is clipping because of the page zoom.
When the page zoom is <=100 then the barcode and images are rendered correctly on screen, but as soon as the zoom is above this (125% on page width) the bottom of the barcode is clipped and the shapes are messed up too.