The chess editor (the brown checkerboard in the box you are using, allows you to set up chess diagrams or games. I however am having many problems with it. My biggest concern is that it does not allow me to enter my entire game cutting it off around move 30. This is infuriating because I only learn this after working on annotating for 20 minutes! Why does the editor not allow unlimited # of moves? Also, how do you upload a pgn string into the editor? The program won't let me browse and upload it.

When your moves are many, just scroll down and they will be shown (look for scrollers on the right side of the window).  You can actually put many moves there.  When you start the editor's wizard, choose the PGN radio button.  Open the PGN text file (using your favorite text editor, maybe it's Notepad or gedit) and copy all the text to your clipboard, and then to back to the wizard window and paste the text at the text box provided (type Ctrl-V in Windows), then continue with the wizard.  You don't upload the PGN file, you upload the text in the PGN file.  I hope that helps. 

Also you can input all the moves first and then go back and click on the first move to start annotating the game so that you do not waste your time like what happened to you before.