Ok, so I was able to fix the issue with the Developer name being listed twice in the title for the glass theme. I've only done this for the Glass Detailed theme but I suspect it will probably work for the regular glass theme too. This should only be done temporarily until the theme's developer can properly fix this. Make sure you've exited out of BigBox before doing this.
Head to \[LaunchBox folder location]\Themes\RetroFresh Detailed - Glass\Views and open GameDetailsView.xaml in a text editor, like Notepad. On line 36, you'll find <TextBlock Text="{Binding Path=SelectedGame.Developer}" . (Just use your text editor's search function for this if you can't see lines numbers.) Change the word Developer to Name. Save the file and that's it.
Hope this helps!