Hi Stephen
I've set up this system both at home and at work and I had the same issue when I set it up at home. Now, I can't remember the exact procedure but I vaguely recall that I had to publish the "Project" form as one to be used in the new 'Projects' folder I had created within Outlook, rather than just as a standard 'Contacts' form. Unfortunately i can't double check this as i'm at work at the moment, but I hope it might help in some way.