SOLVED CKeditor Plugins (6 Questions)(& switching to CKeditor 4)

[Arugula]

@Raeven, @Shawn, Thanks so much for both of your info. There is no current documentation on this, so trying to guess the syntax is difficult. This info should be added to the main docs. Anyway, got Raeven's line to work with config.extraPlugins = 'youtube';
But you're saying I can't add more than 2 plugins with this code? I don't fully understand the new push/join stuff; never heard of that in code before. But I'll try it too. (I'm working the next few days, so I may be slow to post).
@Shawn: Any info on how to get autogrow to work? UNcommenting the extraPlugins.push('autogrow'); fails to do anything for me.
Thanks.