Please consider changing variable name 'language' for frontend ctransifex download links as it conflicts with some language related code or extensions !!

What happens is that the download controller of ctransifex component gets a value of ZERO for 'language' URL variable because the variable is set by other extension to e.g en-GB and then converted to int

the final result in frontend is an exception with "Something went wrong"

Also maybe replace the exception "Something went wrong" with :
JError::raiseWarning(500, 'Language pack for language with is: '.$langpack_id.' was not found');

Regards