[NTG-context] Tikz figures not centred

Hi, I've been having some problems with tikz figures. When I define a new tikz figure, I normally put it in a buffer: \startbuffer[mypic] \starttikzfigure ... \stoptikzfigure \stopbuffer which I use later when I place the figure \placefigure{My picture}{\getbuffer[mypic]} The problem is that the figure is not centred: it is always aligned with the left side of the document. I guess this has something to do with Context not being able to get the image bounds, since it works fine for tikz images that are already precompiled into PDFs: \placefigure{My picture}{\externalimage[mypic.pdf]} Minimal example is attached. Michael. -- Michael Murphy University of Ulm