Adding Webparts Using An XML File?

I have followed this link and it seems to work in the sense that it adds webparts from my XML file successfully.

[URL]

However, the actual controls themselves are never displayed and their respective page loads are never called.

The controls themselves work fine if I hardcode them into the catalog zone and inherit them from user controls but when I change their inheritance to webpart and try and use the control from this example, as mentioned nothing appears. Clear as mud?

An example of a control -

public
partial
class
hello :
WebPart
{}
<%@ Control
Language="C#"
AutoEventWireup="true"
CodeBehind="hello.ascx.cs"
Inherits="Controls.HomePage_Controls.hello"
%>
<asp:Label
ID="lbl1"
runat="server"
Text="Hello"
Font-Bold="true"
Font-Size="Large"
ForeColor="Blue"
/>