1d. Dreary company ? Don’t scowl so much ! (10)
C***U*****
9a. Song , mostly fiction (3) **E
13a. Rent small room someone vacated for free (3 , 5)
**T/*O*S*
17a. One may hold coffee and walk nonchalantly , on a mobile
(6) **C*E*
Alwayspuzzled, ChrisE - It has to be Let Loose, the L(et) coming from the Colourless. (You wouldn't have known those crossed, but I still have my copy.)