1. Are you interested in taking up your case or her case ?
If you are keen on getting a clean chit for you against the adverse report made by her in the annual appraisal report, then you should concentrate on highlighting your own merits and may point out her mal-intention behind her report.
You can bring to the notice of the authority concerned that she is intentionally doing this to wreak vengeance on you for the reason that you had made a complaint against her in the past and the management found her guilty, etc.
You may enumerate all those things that had taken place in the past the action taken by the management on this.
2. No legal case can be initiate agaisnt this until and unless yo have evidences in black and white to prove her reports are false, but by then you will be sacked by the company for seeking legal help without exhausting the remedies available within the company.
3. Read the 1st answer above, instead of taking action against her, you should concentrate on the relief that you require now.
4. There is no question of defamation.
Her false report about your annual appraisal report do not constitute any element for filing a defamation case.