I recently converted one of my books into an iBooks format using Author. However when I connected to my iPad and went into 'preview', I saw my device, clicked it, but the 'preview' button to enable the previewing process was faded and I could not click it. Has anyone actually used the preview feature enough to give me some help? Thanks!
Had the same issue with my iMac running Lion and iPad 1. The iPad was visible but greyed out, as was the preview button.
Here's what worked for me:
Not sure why or how, but it worked for me.