Hi Jeganathan,
Some thoughts come to mind;
Do you want to publish just an image of the process, or the actual BPMN model file or both? The image is useful for just visualisation, the model file is useful for more than visualisation. Gievn you talk about a process repository, perhaps both would be a good idea.
The modeler works with BPMN files, hence you can move the file around independently of the modeler. There are quite a few ways to render the BPMN file to either an SVG or PNG image which is just another file...You could also check out
http://bpmn.io the demo allows you to upload BPMN files and render to SVG files...
regards
Rob