RadEditor uses the Rich Text Editing engine of the browser, the default behavior of which in Internet Explorer is to apply the indentation and alignment to the whole paragraph rather than to a single line/word of text.
Review the following KB article http://www.telerik.com/support/kb/aspnet-ajax/editor/applying-indentation-or-alignment-per-line.aspx
In addition you can review the following two online help articles:
1. Set Properties Via Config File
2. Defining custom CSS styles
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