Just give it a little bit of time for it to adjust to the new environment. Our skunk cleaner did the same thing, hid for the first 2 or 3 days until he got used to where he was. Now, he's all over.
You did acclimate him first tho, correct? Because they are sensitive to changes in water....and it is a very good possibility that your tank water is not the same as the LFS's water.....