WebERP Change Language does not work

[ZHCY.CN]

I want to change the page languate of WebERP to another language(zh_CN),but it is not work.
Ways what I've tried:
1. change the setting in "User Settings>>Language"
2. modifiy the config file of WebERP located in "Web\webERP\config.php ", change the variable "$DefaultLanguage"="zh
_CN" or "zh_CN.utf8"

System:QTS 4.5.3.1697
Software:WebERP 4.13.1.0.1

Is there any other ways can I change the page language or any mistakes in my operation?
Thanks in advance for any advice.

[dolbyman]

maybe try 4.15.x from here

https://www.weberp.org/

and check with the developer for bugs/issues