Bruce Silver is still carrying the torch for BPMN2 interchange - thank goodness someone is- and has yet another update to explain the ins and outs of "valid" models.
That means an interoperability validation tool needs to test, in addition to the normal semantic rules of BPMN, rules that relate the semantic and graphics elements.
For example, the rule in question here might be something like this:? In a diagram (i.e. page of the model), if a process is represented by a pool then all elements of that process on the page must be enclosed within the pool shape.
It is going to be a long road to get there but Bruce is, at least, making progress and uncovering some of the semantic (as well as syntactic) issues.
And since it took me a while to publish this post, we have an update from Bruce regarding BonitaSoft:
I have run across 5 BPMS vendors interested in my BPMN-I work: Activiti, BonitaSoft, Oracle, SAP, and IBM.? Of the five, BonitaSoft is so far the most successful in actually implementing BPMN 2.0-based model interchange.? Not only that, they are the only one so far that has implemented any of my suggestions for conforming to the xsd and BPMN-I.
I've said it before, I'll say it again: when it comes to interchange, I think open-source offers the best alternatives.? Activiti was probably first occupied by providing an upgrade path to folks running JBPM3 and 4, rather than from other BPMN2 tools (very few of which yet export proper BPMN2 XML).
I'd agree with Bruce's assessment that so far, BonitaSoft does the best job importing someone else's BPMN2. In a project last summer we exported JBPM4 to BPMN2 (via an xsl transform) and then loaded that into BonitaSoft, and while we ran into a few issues, we could only get BonitaSoft and Oracle to import BPMN2 at the time. Unfortunately for Oracle we had to add quite a bit of custom Oracle decoration to the XML to get the diagram to show up decently.? (BonitaSoft has an auto-layout feature that helped).
(note: another update from Bruce)