They seem to be getting acclimated to their new homes. Remember, they're pretty shy so they'll tend to hide more until they get more comfortable.
They say that the first few weeks are the most critical with Otos. I guess it's because they are fairly delicate and are sensitive to travel and new surroundings. As long as their little bellies appear to be full, they're eating and acclimating....They should be fine. Mine have huge little bellies (I know, an oxymoron

) on them and skitter from place to place all of the time.