Hi Tihomir,
I heard that currently with the new Gurnor interface, one could configue only shows the editor with save buttons, which will save it to .bpmn file. But I could not find detailed document on to make that work.
If you can share the steps to do that, it would be great. Also, what is the difference between that one and the task you are working on?
BTW, I used http://localhost:8080/designer/editor?profile=drools, it worked without the saving failed error.
Thanks.