Luci themes: What's the logic the Theme applies on Openwrt MVC system?

I am desining my own theme of OPENWRT R21 version.
I rebuilded the sysauth.htm which is the logging page and stored this files in my own directory the path is: /view/themes/myTheme/sysauth.htm.
the system's original sysauth.htm was stored in the path /view/sysauth.htm.
When I was doing the work locally, it worked fine that the system will render my own sysauth.htm file in priority rather than his own original file, but after I compiled my theme into IPK and installed on the other OPENWRT system with the same R21 version, the system prefered to use its own sysauth.htm template file rather than mine, and the my layout was broken saddly.
Thus, I was wondering are there any logics that the MVC system applies to? and how could I get my own sysauth.htm work as default or in priority?
Thx!