Can't export selected scenes

I’m trying to export part of my storyboard. About a 1 minute of a 25 minutes storyboard for an animation feature.But everytime I select the scenes, on the select button of the export window. The export button greys out.I´m trying to export a quicktime of about 28 scenes of my SB. How can I do it?Thanks in AdvanceMauricio

I renamed the scenes, and then it worked.Since there was some scenes named with “_1_1_1”. Because I made several cuts on my project. I Suspect that the names of the scenes was more than the select string could handle.