I've upgraded from Sencha Touch 2.0.3 to 2.1 in the hope that performance will be improved for the Android app I'm working on and have encountered the following issues:

-- the function setTabBarPosition() is no longer working or is extremely buggy. I am trying to move the tabBar from left to right.

-- Pull to refresh, which was working before now causes a javascript error so I have had to comment it out to get the app working. Code and error follow.

plugins: [
    xclass: 'Ext.plugin.PullRefresh',
    pullRefreshText: 'Pull to refresh',
    refreshFn: function(plugin){
        MyApp.app.story_offset = 0;
    MyApp.app.story_limit = 10;
    params: {
        start: MyApp.app.story_offset,
        finish: MyApp.app.story_limit
    callback: function(){
        Ext.each(Ext.query('.post'), function(post){
            post.style.display = 'inline';
            Ext.ComponentQuery.query('storylistpanel button')[0].show();
The error in this case is
Uncaught TypeError: Cannot call method 'insert' of undefined

-- I have also had to replace 'jsonpcache' with just 'jsonp' as including the former would result in build errors when attempting to run 'sencha app build package'. The error is attached as a text file (too awkward to paste in here). Text file will be pasted in next post. I cannot attach as I do not have permission.

Has anyone else here encountered these problems. My questions are:

-- Has Pull To Refresh been replaced? If so, what replaces it?
-- Has anyone encountered the same problems with jSonPCache? If so, can they be fixed?