Yes, from 5.3 boundary events are supported on tasks. Looking at your process it seems like there is not timer definition given:
<boundaryEvent id="boundaryEvent_1" name="Boundary event" attachedToRef="userTask_1"> <outgoing>sequenceFlow_4</outgoing> <timerEventDefinition id="timerEventDefinition_1"/> </boundaryEvent>
and it should look like this:
<boundaryEvent id="_4" name="TimerEvent" attachedToRef="_2" > <timerEventDefinition> <timeCycle xsi:type="tFormalExpression">500ms</timeCycle> </timerEventDefinition> </boundaryEvent>
once you'll fix the process definition you'll be able to execute boundary events on a task.
Thanks Maciej. That did the trick.
I didn't put in the definition earlier because I was creating a script that automatically included other required nodes (e.g. message, operation, and item definitions) based on the activities in the process. The process file I attached was actually an output of that script. It looks like I also need to automatically include a timeCycle node when I find a timerEventDefinition.
The only item I'm stuck now is how to get two start nodes to work (one "normal" start and one message start).
Again, many thanks for your your response.
For multiple start events you need to wait for 5.4 version or use snapshot version from master as it was introduced quite recently.