[2005] Designer support for template controls that include other web controls

[SLH]

I have developed a templated web control that has 2 templates that instanciated in controls that are in an updatepanel.

To do this i've got a private member, updatepanel, 2 private ITemplate members and 2 private container controls.

The trouble is when i want to add designer support. If i add the required designer code:

public class TemplateControlDesigner : ControlDesigner
    {
        TemplateGroupCollection _TemplateGroups = null;

        public override string GetDesignTimeHtml()
        {
            return "Click here then use the top right icon to edit the templates.";
        }
        public override void Initialize(IComponent component)
        {
            base.Initialize(component);
            SetViewFlags(ViewFlags.TemplateEditing, true);
        }

        public override TemplateGroupCollection TemplateGroups
        {
            get
            {
                if (_TemplateGroups == null)
                {
                    _TemplateGroups = new TemplateGroupCollection();
                    DeferredLoading control = (DeferredLoading)Component;
                    TemplateGroup group;
                    TemplateDefinition template;

                    group = new TemplateGroup("Templates");
                    template = new TemplateDefinition(this, "Loading", control, "LoadingTemplate", true);
                    group.AddTemplateDefinition(template);

                    template = new TemplateDefinition(this, "Display", control, "DisplayTemplate", true);
                    group.AddTemplateDefinition(template);
                    TemplateGroups.Add(group);
                }
                return _TemplateGroups;
            }
        }
    }

When in design mode it allows me to add controls to each of the templates, but not plain text for some reason. Also, whatever i add in design time when i switch to view the markup it's replaced whatever was there with an updatepanel (when it should be the 2 template properties).

I've tried only creating an instance of an update panel if not in design mode, however then the designer gives an object reference not set to an instance of an object.

Any ideas would be great because i'm really stuck here. I've tried searching but as i'm not really sure what to search for besides general 'how to make a templated control' i'm not getting anywhere.

Any ideas??