Logon with FBA to Project Server and call PSI methods programmatically

Hello there,

I am trying to get a "GUID" of a project by passing a "project name" to "ProjectDataset's" object via reading a available project list via a method of "Project" class (PSI). But as I am using form authentication for my PWA, so I am not able to logon to the PWA and read the project list. The purpose of doing so is to create approval task for project server 2010 workflow in visual studio 2010.

I hope, I am able explain it properly, please guide me as soon as possible since it kind of urgent requirement.

Thanks in advance.