One important operation I've noticed in the examples that do end up with abiogenesis is having a 'copy' operation. In the bf version they use in the paper, one head can copy the byte under it at the location of the other head. Which makes it quite easy to make a self-replicator: just loop on the copy operation and move both heads, essentially (5 instructions). You could try adding the 'copy' operation to your setup and see if that helps!