Default Guys help me please..I need your advice

Hey guys..
Around 3 or 4 days ago I downgraded my galaxy s3 from 4.4.2 kk to 4.3 jb and that because of many reasons like random reboots lagness and ram problem and I'm so happy with jelly bean
I u glance note 3 4.3 rom but I miss the my files,music app and light blue colour in s5 rom so my question is..
can I replace my current my files with kk s5 my files ?
Can I do the same thing with music player?
Finally...Can u guys give me a link to have that nice Blue colour in my mobile and thanks for your careness

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