for what I do is Lego block container with a foamcore base. the bases I am casting are glued to foamcore with enough space between them to allow flex. I then brush my silicon over the bases entirely to coat the part, and then pour the rest in from far up to "degas" with a thin ribbon stream. let set up and then Im done. Mix resin, pour, repeat
Im SURE you know what your doing BUT this is a nice pamplet made by Micro-mark I ALWAYS have beside me to remind me of silly mistakes i normally forget (like mold release between the sides of a two part mold.... )