[Plugin: WordPress Mobile Pack] Change main menu

Hi, i use the FlatOn theme and i have customized the css files so that the website can fit with my preferences. After finishing my website, in mobile version was really terrible.. ??
with the plugin WordPress Mobile Pack got it working properly but i need to edit the main menu. Currently the main menu is:
GO TO->
my menu
OTHERS->
-Visit Website
-Credits
and i would like to transfer the “my menu” in main menu..

searching for some older issues
([resolved] Use a different menu for Mobile Theme)
, but in Appearance -> Editor -> there is no option “WordPress Mobile (base)” where you select theme. There are only my uploaded themes that i tried to used when i was searching for the propriate theme to edit.
what can i do for changing the menu in mobile?