Hi Jeffrey,
If there were some exception during jobExecutor executed jobs. It will store the related exception information into database. We could get these error information by querying JBPM4_JOB tables.
Then if you want to execute some jobs by hand, you could use management.executeJob(jobId);
At last, I think the best way to handle the error in process is using exception-handler, which is not implemented yet, Did you have any advices on it? If you have any advices please tell us, Thank you very much.