adding restriction to CPT Redirect

Hi !
I saw the following topic about adding the functionality of restricting content for CPT
but I dont know how to do the same for my site..

http://www.gojournalism.ca/ is my site and we need the write a story page to be restricted to make sure that people log in before they write a story.

I tried if else statements with redirect, but it keeps saying headers are already added etc.. please help me with this same

also .. I would like the login / register to redirect back to the restricted page. is there a way of doing it ?
Please help me as soon as you can, this is a school project and we are approaching a deadline so we reallllly need it soon !! thanks much appreciated…

please let me know what do you need for us to provide to help us better..
note: write a story – uses personal fundraiser plugin.

thanks
namita

http://wordpress.org/extend/plugins/wp-members/