At the top left corner of Editor, as shown in your figure, there a dropdownlist having Label Style Use can use this DDL to apply the style on the text written in the editor.

Just select that text and apply the style on it.

As I did in this "Sample Style 1 from DNN site". I applied "Custom bold" CSS class  on this text.
"Sample style 2 From DNN site". I applied "Custom Bold" CSS class on this text.

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"Knowledge Sharing Matters!"

Hi there,

I've just encountered the same problem. I solved it by changing my style to reference the body by ID instead of tag. The iFrame inside the FTB control does not give it's body tag an ID.

i.e. I replaced -
body {background-image: url(background.gif)}
with
#Body {background-image: url(background.gif)}

Cheers,

Andrew