Your art is improving a lot, good work! I think for CC you should go back and read the CC previously given to you in the past and still apply it to your current pieces. There's a lot of solid constructive criticism given in this thread, which is really great (this is what I love about our graphics community, there's always so many people willing to help).
However... although I can't speak for the artist community as a whole, IMO stealing/editing someone else's work without getting their permission and crediting them is something extremely
off limits here. I don't think I need to explain why since there's already a great thread Latte made on this (give this a read: https://www.graalians.com/forums/showthread.php?t=24770
Not only will this deter other artists from wanting to help you improve in the future, but the servers hiring artists are definitely
going to go through your track record. If they find you stealing... well, that's going to give you a major disadvantage when it comes to who they want to hire.
TL;DR Don't steal other people's art. Especially, you should own up to it instead of brushing it off.