I am trying to use the 'onimage' environment listed here: 
http://tex.stackexchange.com/a/30435/50081
to be able to point-and-click nodes onto an image. I followed the instructions 
of installing the onimage.sty file in the appropriate folder as listed here: 
http://tex.stackexchange.com/questions/229711

I use this TeX-snippet:

\begin{tikzonimage}{example-image-a}[tsx/show help lines]
    \draw [orange, line width=5pt] (0.5,0.92) circle [radius=0.75cm];
\end{tikzonimage}


The image is correctly shown in the preview. I would expect to be able to click 
on the preview image to create new nodes. However no new nodes can be produced 
by clicking there. Only after I wrap the snippet in

\begin{tikzpicture}

\end{tikzpicture}

new nodes can be created. BUT: The image keeps jumping around and makes the 
procedure pointless.

I am using Windows 8 and MiKTeX.