I wanted to respond to you question regarding corn tortillas.
The corn meal you mentioned would not produce the same
tortillas that you would find in Mexico or readily availabe here
in, especially the southwest, of the United States.
The big white dry corn kernel are generally used to make "masa", but first must first undergo a slight chemical treatment before it becomes "nixtamal".
"Nixtamal" (the precursor to masa) is made by first adding water to a pot, then the big white corn kernels. Next you must add what the Mexicans call "Cal". This is a mineral called Calcium Hydroxide (also called "lime" not the fruit!). The water, corn and "Cal' are heated and boiled for a period of time.
The heat removed and the mixture is allowed to soak for various lengths
of time. the soaked corn is allowed to cool and the skins are removed from
the kernels with the little pointed end as well.
This "Nixtamal" is then ready to be ground into "masa".
The amount of moisture varies, but your lokking for something
that can be patted or pressed into a thin flat cake, baked on
a "comal" (comals are another complete topic) or cast iron frying pan.
At this point it is ready to be made into "tortillas", and/or
many of the shapes, such as, "gorditas", "sopes", "huaraches",
"chalupas", 'empanadas", and the regional names go on and on.
I'm not sure if you can buy this type of corn there in South Africa?
If you can purchase some "Masa Harina", you can make your tortillas
as this mixture has already gone through the "Nixtamalization" process then dried and ground.
I hope this helps, and good luck with your "tortilla" making.
"aficionado de la cocina mexicana"