1.How do you change workflow attached to orders?

Workflows can be attached to header or lines from transaction types setup window.


2.How do you start the workflow from concurrent manager ?

Step1:
Initiate the instance of the workflow using wf API wf_engine.createprocess

Step2:
Set the item attribute values and start the wf using
wf_engine.startprocess API

3.Can workflow we can send email with forms6i screens?

Yes

4.Can workflow take actions based on notification response?

Yes