nodes with "pure" ancestors (have no predecessors) cannot be start nodes
Fix bug: nodes with "pure" ancestors (have no predecessors) cannot be start nodes
The bug had nothing to do with submodels. Basically in workflow12 the IN node of the submodel was considered a start node because it had all information to start. This meant all required input is available before running anything and it has only conditional predecessors. However these criteria for being a start node were not enough.