What should you do if you arrive at a locus and it's empty?

Reconstruct from the neighbours and the encoding, then re-stage the image more vividly so it holds next time.

A blank locus means the image was too weak (bland, static, non-interacting). Recover it by: using the surrounding loci and the logic of the material to reason out what should be there, confirming it, then re-placing a bolder, interacting image at that spot. The empty locus is feedback — it's telling you exactly which image to strengthen.