2 Sweat67 from developer, Locked language resources

By default, system resources are locked by OS X.
In case your resources are locked, you should unlock them manually in order to clean them up.
See instruction link in the applications description.

All The Best,
Serg

P.S. Resources can contain up to 50 additional language items (Afgan, Romanian, Chinese, etc.).
If you need all of them you can skip this step, just remove others.

S.K_1 about Clear Disk Space: ClearDisk