Cannot save model through store

I'm sure this is pretty basic stuff but I'm new to Sencha Touch and could use some help.

I'm using Sencha Architect and have created a "Users" store and a "User" model:

Code:

Ext.define('APP.store.Users', {        extend: 'Ext.data.Store',


        requires: [
                'APP.model.User',
                'Ext.data.proxy.LocalStorage'
        ],


        config: {
                autoLoad: true,
                autoSync: true,
                model: 'APP.model.User',
                storeId: 'Users',
                proxy: {
                        type: 'localstorage',
                        id: 'user_login'
                }
        }
});

Code:

Ext.define('APP.model.User', { extend: 'Ext.data.Model',


        requires: [
                'Ext.data.Field',
                'Ext.data.proxy.LocalStorage'
        ],


        config: {
                idProperty: 'user_login',
                fields: [
                        {
                                name: 'user_login'
                        },
                        {
                                name: 'user_data'
                        }
                ],
                validations: [
                        {
                                type: 'email',
                                field: 'user_login'
                        },
                        {
                                type: 'presence',
                                field: 'user_login'
                        },
                        {
                                type: 'presence',
                                field: 'user_data'
                        }
                ],
                proxy: {
                        type: 'localstorage',
                        id: 'User'
                }
        }
});

The following works to save data and to be able to look it back up again:

Code:

var user = Ext.create('APP.model.User', {
        user_login: 'user@address.com',
        user_data: user_data
});
user.save();

// some time later
var UserStore = Ext.getStore('Users');
var value = UserStore.find('user_login','user@address.com');
console.log(value); //returns 1 (index of found entry)

I assume that I should be saving this to the store as follows instead of directly working with a model:

Code:

var UserStore = Ext.getStore('Users');
var UserToAdd = { user_name: 'user@address.com', user_data: user_data };
UserStore.add(UserToAdd);
UserStore.sync();

But when I do it that way it doesn't save to the localstorage and cannot be pulled up again.

What am I doing wrong?

Should I continue doing it the way that works but looks to be the "wrong" way according to docs? or should I do it differently?

Am I completely misunderstanding how stores and models work?

Thank you.

Cannot save model through store