RV Dynamic Slideshow - Thumbnail Area Control

Press F11 to Open Library, search for Description folder and open description movie clip

Choose the textfield inside description movie clip. Click Embed in property panel, select all characters that you need to use and click OK.

Since the font is Embeded Arial, you have to open Flash and change the Font property in description textfield inside description movie clip (see above), also you need to change the font-family property in CSS file.