Re: do cockroaches have biological clocks?

Yes. Almost all, if not all, organisms have some sort of biological clock.
Even a lot of bacteria have biological clocks.

As to the route these creatures take each night, I'd guess their repeat
performance and repeated behavior is due to a combination of memory (yes,
roaches DO have memory) and pheromone/scent trails. Also, roaches have a
strong thigmotaxic behavior- they like to be up against things so they
would move from where they live to where they are going- probably to feed.