I read that it is necessary to accrue 31.250 miles or traveling at least 50 times on *A operated flights within a 12 month period to be silver and to accrue 50.000 miles or traveling at least 80 times to be gold.

The mileage accumulated in your Frecuenta account, as well as the Mexicana and Star Alliance network Code Shares, will be taken into account when determining your status within the program.

From the wording "mileage accumulated" I am pretty sure that all miles (eg class of service & tier bonus) are counting for status (re)qualification.

Further more, miles earned eg on credit cards, car rentals or hotel stay should also be eligable for status qualification. This should be to good to be true...