The RadEditor cotnrol's new line mode is changed to add paragraphs by default in 2014 Q2 version.
This is done to provide a behavior more consistent and more desktop feel of text editing (e.g. MS Word). In most browser you should be able to still add a BR (carriage return) using the Shift+Enter
shortcut, just like in MS Word.
To revert to the previous behavior you can set the NewLineMode="Br"
property and force the editor top add BRs on each Enter press. Note that in this case the user can add P elements only using the Insert Paragraph tool or in using the Ctrl+Enter
Check out the Telerik Platform - the only platform that combines a rich set of UI tools with powerful cloud services to develop web, hybrid and native mobile apps.