Looking good. Dont stand still for too long or they'll tie you into the slab  

Get some tape on the open ends of the UFH pipes asap, and slide down some 25mm wall 15mm pipe insulation so you have some wiggle room for when the manifold is to be connected. Have the insulation about 300mm below slab level and about 200mm left showing above.  

What Nick said, for sure.

 

For neatness, consider spacing the pipes as accurately as possible where they come out of the slab before the pour. No big deal, but it does annoy me that mine are slightly crooked and unevenly spaced.

Our manifold was connected up to a board at the time of laying the pipes