Electrical installation instructions are not law, but can be used in a court of law, and odd as it seems just under the ceiling around the room is considered as a safe zone, but at floor level it is not, unless some thing shows there are wires there, so using skirting trunking is OK, but home made skirting trunking is not, which I know seems daft.
Using cable buckles and having the cable visible on the top of skirting is OK, but hide behind skirting is not, which I know seems daft, if there is some electrical item then vertical and horizontal from the item is a safe zone, so skirting with lights set in to it and cable behind would be OK as lights show there will be a feed cable. But it stops at any corner.
It is all down to safe zones and where one would expect to find cables.