Where is this video located? Did you use Premiere Elements' Video Importer to get the video from the camcorder to your computer? (If the video is still on the camcorder and you disconnected the camcorder, it will go blank because the program no longer has a connection to your original video files.)
I did use the importer (after I loaded the video on the PC's hard drive...)
First, some GoPro notes...
Second, some learning help...
Online User Guide http://help.adobe.com/en_US/premiereelements/using/index.html
-Page to download current PDF http://helpx.adobe.com/premiere-elements.html
Importing Video http://forums.adobe.com/thread/1065281
-and project settings http://forums.adobe.com/thread/1112086
Saving & Sharing http://forums.adobe.com/thread/1137128
-Sharing to DVD or BluRay http://forums.adobe.com/thread/1137645
-Sharing for Movies http://forums.adobe.com/thread/1051093
-Sharing for Computer http://forums.adobe.com/thread/1058237
Steve's Basic Training Tutorials... steps are the same for several versions