How to properly make a runnable jar/exec? [Solved]

My current process was to export the java project as a jar file from eclipse:

http://puu.sh/31ydm.png
(Said that there were some compile warnings)
Then I used Jarsplice:
Added all the necessary Jars -
http://puu.sh/31xY9.png

Added all the natives -
http://puu.sh/31xZx.png

Added the main class and made a fat jar from all of that…

The problem is that it goes to the login screen fine, but when I click login or play offline, it goes to the loading screen window, but abruptly closes.

I have no clue what the problem is :S

(Works fine from eclipse:
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