BMG – no use sending you some waypoints then!
Babymaker etc are South of Surrey Hill – easiest way (but dull) to get straight there is to head South then East when you can from the Lookout and follow the bleeding great mess of a fire road that's left over from the water main works & runs pretty much North/Sotuh. Go past the reservoir (though a detour to the East at the reservoir could be rewarding) staying on the main fire road then up the Wall (you'll know it when you see it) and the Babymaker etc is on the LHS/E after the fire road (about 891633 if you've got an OS map), but there are a couple more trails on the LHS before the fire road. On the way down from the reservoir there are a couple more trails on the LHS too, and the entrance to the Rollercoaster is a gap in the wire fence/hedge on the RHS (go in & turn right).
If you do a right on the fire road at the Surrey Hill reservoir there are a few other short runs that go off to the RHS down towards the jump track.
Happy hunting.