My Gallery slideshow viewer thing

So, I just got a replacement Droid 4 and it has erased everything on it so I have to start from scratch. I have to questions regarding the My Gallery app thing that comes with the phone:
1) How do I get it to only display my Youtube subscriber updates and NONE of my facebook friends updates? I used it on my old phone as a place where JUST youtube stuff was, not facebook stuff. how do I edit what is shown on the gallery widget on the home screen?

2)How do I get it to be four squares wide and not three? because i accidentally deleted the original thing that was there (it was four squares wide) and now when i reloaded the widget it just sits there awkwardly being only three squares wide.

please let me know. Thanks!