I used a round ceramic dish about the same size as my tortillas. This helped them stay upright and pie like. You could use a cake tin if you don't have a ceramic dish. You could also use gluten free tortillas.
The tomato sauce doesn't need to be reduced right down or you will not have enough sauce for the 9 layers.
Just a bit of sauce on each layer is enough.
Don't skip the cheese between layers
The tomato cream sauce should be reduced enough so that it becomes easy to pour over the top of the pie and stay there.
Don't forget to set aside cheese for the top
You can put as much cheese into the lasagne as you like. you could also use other cheeses in between the layers like Farmers cheese, ricotta, feta, mozzarella or anything else you fancy
You can buy mayonnaise and add a bit of lime juice or zest to it
Achiote looks like an orange stock cube and can be reconstituted in the same way