How do I theme the user/uid/edit page?
I found the solution for this.

The reason for error was that the ThemeKey module was not overriding and admin pages, by default.
Hence pages like user/uid/edit which are admin by nature are not overriden in their theme and pick the admin appearance theme always.

To bypass this I enabled the THEMEKEY COMPATABILITY Module (Part of Themekey module for D7). Open the following settings page:

http://localhost/admin/config/user-interface/themekey/settings/compat


Section Modules&gt;&gt; Integrate Modules in Theme Switching Rule Chain&gt;&gt;

Then check the option "System (Administration theme)".

Now all admin pages like user/uid/edit also come under theme switching rule and pick the theme as defined.