I have contacted Machinima and they told me that copyright thumbnail can get user copyright strikes! So be aware.
I am the original poster! Anyways like Markkaz stated above dont use copyrighted material as your thumbnail.!Thanks for the info. As for me, I don't want to take any chances
to attract any attention from large companies who have deep
pockets and could make my life miserable.
To the original poster, just use your own images and you will
be able to have pride in that you're doing the right thing.