The Auto-Layout does not create associations correctly. It would not be too hard to allow this, I did a quick hack to achieve it in this branch https://github.com/camunda/camunda-bpmn-model/commit/d38346380126113c1cf3cd3ae4cb737600ee03fa.

Aut-layout should be able to draw this correctly. Otherwise you have to hack around a lot to do auto-layout for these elements (see e.g. https://github.com/flowing/flowing-trip-booking-saga/blob/master/src/main/java/io/flowing/trip/saga/camunda/SagaBuilder.java#L128).