I think it's best if I spend a small amount of time actually reading the post properly and looking at the pictures. My actual opinion is as follows. The cooker cable running horizontally is out of the prescribed zone, which can be seen from looking at the picture posted earlier. The regulations require the cable to be run in the prescribed zone in order that an RCD complying with the specification provided in BS7671 for an RCD intended to provide additional protection may be used as an alternative to mechanical protection, as described in chapter 52 of BS7671. As for providing covering for the cables - I think it's unlikely that a plasterer would cause damage to the cables seen in the pictures with his trowel and although I personally would have covered the cables with capping instead of oval tubing, it's at the discretion of the installing electrician, having assessed any potential for damaging cables, how he chooses to protect cables from damage during installation.