Coconut flour may not be necessary - its only purpose is to absorb some of the moisture from the mix, which will be more or less dry depending on the ricotta brand and how much water you squeezed out of the zucchini pulp. Use your judgement: if the filling mixture is a thick paste consistency, you can omit the coconut flour.
You can definitely bake these in advance and enjoy them either re-heated or cold.
The only way to ensure accurate measurement of ingredients is with
Metric Kitchen Scales (U.S. option
HERE).