In stock Angels Smelting for 0.18, the casting machine has 3 input fluidboxes and 1 output fluidbox.
ShinyAngelsGFX changes it to 3 input fluidboxes only. It does this when changing pipecoverpictures() to pipecoverpictures2().

There are recipes in Angels Industries that rely on this, in particular the Motor Casings with the reusable molds.

I added the missing output fluidboxes in data-updates.lua and this fixed the broken recipes.

My first attempt made the recipes fit but I must have missed something as the output fluidbox won't output. I ended up completely removing the fluidbox overrides from the four casting-machine variants and that fixed it.

What is the override for? pipecoverspictures2() seems to just use the base game graphics. So far, I haven't been able to spot any visual difference with the override removed for the fource casting-machines.

There is still an issue with this as a follow-up. I've commented on the forum post as well, whichever you prefer Zombiee.

I've made a patch mod for this in the mean time: https://mods.factorio.com/mod/ShinyAngelGFX-casting-machine-patch