I absolutely love this mod, been having a blast figuring out all new ways of making old boring things (like green circuits), especially when combined with something like Bob's adjustable inserters to make super compact builds.

I only have one real complaint, and that's that I can't use productivity modules in the assemblers (or at least the Z assembler). It just seems a bit silly - the machines themselves are already super fast, so there's no need to add speed modules, and I can count the number of times I've used efficiency modules on one hand. I do agree that putting four productivity modules in a Z-machine would be way too OP, but the fact that there are two module slots and I can't use them for productivity modules makes it so there might as well not be any module slots.

Actually, now that I go to actually attempt it, I can't seem to put ANY modules into the module slots. Maybe a bug?

I also can't set any recipes that use fluid crafting on the Z-assembler, though it looks like it should support them

I've submitted a pull request on the github repo to fix modules not working in Assembling Machines X and Z. The "allowed_effects" property was not defined, so the game didn't know which module types were allowed, so didn't allow any.