Upgrade Issue

I tried to upgrade my app currently using 4.1.1a to 5.0. I am not using sencha cmd, so I enable compatibility with below code in my index.html,

Code:

<script type="text/javascript">
        var Ext = Ext || {};
        Ext.manifest = { 
            compatibility: {
                ext: '4.1'
            }
        }
</script>

Then I include the extjs css and framework in the the same html,

Code:

<script src="ext/build/ext-all-debug.js" type="text/javascript"></script>
<link rel="stylesheet" type="text/css" href="ext/packages/ext-theme-classic/build/resources/ext-theme-classic-all.css">

The ext folder contains the extjs5 framework and the above mentioned classes.

Assuming everything mentioned above is enough for the app to use ExtJS 5 framework. I start getting errors and console messages. My question is how do I find replacements for the classes that have been removed and errors are being thrown. Is there any documentation available for this OR do I need to figure them out through APIs. Example for removals in Ext.draw.Text , Ext.data.validation.