How to insert facts into kSession from a script task of a BPMN2 process flow ?

Issue

• How to insert facts into kSession from within a process flow (e.g. Script Task) so that a Business Rule Task can be executed using those facts during the execution of the process instance?
• If ksession.fireAllRuless() method is called from the class which is responsible for executing the process instance containing a Business Rule Task , is there a possibility that the rule task might get executed before any other task (lying ahead of it in the flow) attempts to execute?
  e.g. Imagine there is a Script Task which is just ahead of the Business Rule Task in the process flow. Is it possible that if the fireAllRules() method is called, the rule task will be fired immediately and before the rule task node is reached?