No, to get back to k310 you also need to use a custom file from k310.
To upload flash themes you need two files, the .sfw file, and the theme that will call the flash menu.
You then need to inser the .sfw file to tpa\preset\system\desktop\flash, and the theme to usb\themes.
In this thread: Menús Flash para Resolución 128x160 - Top Sony, there's one .sfw with the theme. Use that one to see if you get how to do it.