Even the author of this software says:
"NOTE: It needs to be said that because changing the short username is a serious procedure, you should do it only as a last resort. The best option is to simply learn to live with your present short username. Or, if the account was just created, create a new account with the desired short username and then delete the "unwanted" account. That being said, if you're determined to actually change the short username of an account, read on."
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