Hello,
If you use gwt-console-server then you can call its web services and a little html and javascript to achieve that. The following two do the job,
1). To get the image call http://{your-address}/gwt-console-server/rs/process/definition/{your-process-id}/image
2). To get the coordinates in the diagram of the active node in json call http://{your-address}/gwt-console-server/rs/process/instance/{your-process-instance-id}/activeNodeInfo
Then with javascript you can place an image relative to the coordinates. The gwt-console-server uses the following,
images/icons/play_red_big.png and subtracts 8px from the value of x and value of y for example,
For example,
this is the json [{"width":932,"height":541,"activeNode":{"name":"id\u003d2","x":96,"y":56,"width":135,"height":48}}]
this is the html
<div class="bpm-graphView-activityImage" style="position:absolute;top:48px;left:88px;width:50px;height:50px; z-index:1000;background-image: url(images/icons/play_red_big.png);background-repeat:no-repeat;"></div>
notice,
top = 48px which is 56px-8px
left = 88px which is 96px-8px
so with js you can manipulate the visibility of the div and the left and top values.