Waive Parental Rights – Texas

Please Help. I am in a different country and my girlfriend want to revoke my parental rights and I am for it because I cant get to the States.

I want to know if by waiving my parental rights does that automatically remove my rearrange child support amount. How long does it take to get that done and once I get back to the States can I put it back. Can the Judge not accept it.

Your help will be greatly appreciated.