EnableSanitization removes all of the formatting

I am using HtmlEditorExtender latest version

http://www.asp.net/ajaxLibrary/AjaxControlToolkitSampleSite/HTMLEditorExtender/HTMLEditorExtender.aspx

I also enabled Sanitization

Here my webconfig

<sanitizer defaultProvider="HtmlAgilityPackSanitizerProvider"><providers><add name="HtmlAgilityPackSanitizerProvider" type="AjaxControlToolkit.Sanitizer.HtmlAgilityPackSanitizerProvider"/></providers></sanitizer>

But it even removes

<br>

and it breaks whole formatting

What is the proper way of doing this ?

thank you

asp.net 4.5 c# 4.5

it is supposed to remove only dangerous things