Hi Arun,
Try the start.demo target to complete the tables' creation, at this point you should have 27 tables and the tables regarding human task must be populated.
You must remove the dependency start.human.task from the start.demo target, it raises start.human.task service, this target also runs a class located in
{jbpm-installer}/task-service/src/org/jbpm/DemoTaskService.java, in which you have to comment out the lines of adding users and groups
and not have problems with creating users and groups, and has already created theinstall.jbpm5.