The information provided is insufficient for issue reproduction, so I could give you only general tips for debugging the issue.
You may start by checking if there are any errors when your password change screen is loaded for a new user. In addition, you may download a latest Q1 2015 trial version and check if the issue still persists.
And could you specify what was the version used before the update to Q3 2014?
Last, but not least, the Password Strength Checker demo
and help article
could be a useful reference for you when debugging the issue.
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