EDITING PO during approval

Hi,

We are on SRm 7.1 ECS>

We have implemented PCW for PO approval.We have created the APPRAL TASK as COMPLETION task so all approvers cna edit the PO during approval.

Now reqt is to show the EDIT button only for some approvers.CAN we implement this using roles or is there any setting/config on tyhe workflow to achieve this?

Another reqt is to chnage the subject line for the work item sent to approvers for approving.Currently since the COMPLETION TASK is assigned as the APPROVAL task,the subject line says "COMPLETE PO XXXXX".WE want to change this to "APPROVE PO XXXX".

PLease advise.