I've tried to add Lithuanian language file with some front-end strings translated according to instruction
But on trying to "Load languages" in the backend I have warning message:
These constants exist in Languages files but not exist in file constants:
_BOOKLIBRARY_LANGUAGE_LT not exist in file 'constant' for this language: Lithuanian.
This constants not loaded.!
These constants exist in file constants but not exist in Languages files:
Everything is [ OK ]
And the language constants are not loaded from PHP language file.
I can translate some strings by using backend tools, but that's very tiresome.
Also, I couldn't see file "constant" mentioned in instruction, so maybe it has to be updated?