Solution to Problematic Mexican Timeshares
If you have found yourself a victim of fraud in Mexico the process of getting wrongs against you addressed can be initiated at any Profeco office, embassy, or consulate.
To file a formal complaint with Mexico's consumer protection department (Profeco) - which has a whole governmental section for lodging, timeshare and transportation complaints, you can go to http://www.profeco.gob.mx.
Under the heading at the top that says "Consumidores" you will see a link that says "Atencion al Extranjero" ["Attention to Foreigner"].
Click on that and it will give you the info you need. Or go straight to
http://www.profeco.gob.mx/consumidor/denuncias1.asp#extranjeros and scroll down for the English version.
Here's the link where I found the above information and much more details:
I hope this helps and good luck.