Extracting Apps from Roms

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http://forum.xda-developers.com – If I downloaded a rom from the developers section and extracted an apk like the messaging app, could I then install the apk on my stock rooted phone. I have already swapped out the Touchwiz messaging app for the Pure ICS messaging app found in this forum by pushing it to system folder and setting permissions. Could I do the same for the messaging app in one of the jellybean roms or cyangenmod 10 roms or are they based on different frameworks, etc.? (HowTos)