cannot activate BPF using the 30 day trail version

Guys - before I lose the will to live - Has anyone experienced setting up a business process flow issues using the free 30 day trail.

I am the full admin , I can create as normal but to will not Activate .  I have valuated and checked everything I can think of.

Any Ideas or is this a bug.

I can create standard workflows and do all standard admin things just not business process flows.

Sort of hoping it s a bug as I cant think what else it could be

Janet