For anyone who is trying to use both the JBPM web designer (2.3) and the Eclipse editor (Jboss Developer Studio 5.0.1.GA w/ drools/jbpm 5.3.3.final extension) with Guvnor (which, the eclipse integration with Guvnor within Jboss Developer Studio is GREAT, thank you!):
Errors I've encountered from generating a BPMN workflow in Designer, stored in Guvnor, then pulled into Eclipse, and resolutions (as known). The errors were from Eclipse when trying to use the Eclipse BPMN2 tool on a BPMN file generated from Designer (where designer did not check/protect against certain issues yet), and failing 'RuleFlow XML' validations:
* "more than one incoming connection error" (i.e. merge with a gateway your sequence arrows, instead of directly to a task (BPMN says a task should only have one incoming arrow): https://issues.jboss.org/browse/JBPM-3372
* "Exception when type empty in Convering Gateway" (BPMN says use exclusiveGateway to merge): https://issues.jboss.org/browse/JBRULES-2879
* "Invalid bounds for node" -
* likely a task or node in a swimlane that isn't "all" in the swimlane (make sure fully wrapped).
* a swimlane or other node that is 'outside the margins' (usually too-far to the left)
* "Unable to build expression for 'constraint' null"
* Run Validate button within Oryx/Guvnor, likely quite a few are not validating, correct those first.
* In Guvnor, if start point has 'could not find process image', just click the 'PNG' button to create the image. source: http://blog.athico.com/2012/04/jbpm-designer-version-21-released.html
* XOR gateways that are missing definition.
* To add constraints to XOR gateways in Eclipse, click on the XOR gateway, Properties tab, 'Constraints' field. Need more details/examples.
* To add constraints to XOR gateways in the JBPM web designer, click on the decision-based sequence flow (arrow/line), to add Condition Expression directly to each flow item. Need more details/examples.