Very nice. The last one is a tad over brightened though. And the other ones look good enough, but upon closer inspection the smudging looks odd, but since I fail at smudging we'll skip that for now.
Very nice. :3

Render has pretty good flow though I'm not liking how to the right it is. ALSO, GUYS, REMEMBER THERE ARE OTHER COLORS. Do experiment with fractals and C4Ds as backgrounds/effects though.
Of course. :3

Everything looks fine when compared to the tutorials.
I really do wish that you guys had used more color on the abstracts small piece though. If you're having trouble with that bit just tell me.
Effects look great, even if somewhat whored (tutorials fault, I would say). Also, awesome choice for a render.

Much better. Just remember that with dimensions you don't have to go with big-as-possible every time. Don't be afraid to try different heights and widths. Eventually you'll find something that suits you.

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I'm going to edit this post with tutorials and whatnot later...

@Steve, Rajin: Some of these may be tough, but try getting something out of it anyway:

http://www.gimptalk.com/forum/ninjad...ut-t38874.html
http://geocillin.deviantart.com/art/...orial-86910855
http://daconman.deviantart.com/art/WANTED-Tut-93434062
http://misty82.deviantart.com/art/Bi...orial-68029638
http://www.gimptalk.com/forum/curlyʹ...al-t35719.html

http://www.gimptalk.com/forum/pixela...1;-t38543.html

@Goddess Din, Daltron, Hawke:

http://gimpflare.deviantart.com/art/...s-tut-45229286
http://www.gimptalk.com/forum/time-s...al-t38871.html
http://totalderek.deviantart.com/art...-Tut-107081422

Everyone else I'll get to you later; don't be afraid to try out the above links though.