Bumping this post because I'm going to need to do the same thing. I am a US citizen, living in the US, but was born in Germany. I have a German birth certificate, but not a born abroad document (I assume it's just missing). I also have an enhanced driver's license (allows me to enter Canada via auto) with my new legal name, but wrong sex. AND an expired visa with my old name and wrong sex.
I'm looking for somebody who has gone through the process of amending their born abroad certificate so I can ask them what they actually had to provide.