Sorry for the delay, I don’t have the Grant Full Control Permission action installed on my machine since it is not out of box workflow action in SharePoint Designer.
The collect data from user action can return the task id in the output variable, (see
http://office.microsoft.com/en-us/sharepoint-designer-help/collect-data-from-a-user-in-a-workflow-HA010209808.aspx
for detail) you can later use output variable to lookup the task item and grant permission.
In SharePoint 2010 designer workflow, you can make use the
Only allow task recipients and process owners to read and edit workflow tasks option in
start custom task process action to achieve similar thing and will not rely on third party grant permission action any more.
Gu Yuming
TechNet Subscriber Support
in forum
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