which is the correct firmware and odin required to downgrade my alpha

[Android Central Question]

tried 2 different firmwares and odin fails at the first sequence need to go from lollipop to kitkat

 

[Rukbat]

Any version of Odin should work, from 3.09 to 3.12.7 (those are the only ones I've tried so far). As for firmware, look on SamMobile Firmwares for your model, your country, your carrier. Mixing firmware (flashing a ROM for a different country or carrier) usually doesn't work.