If you’re missing parts, then it obviously won’t work of course, but bear in mind that the diodes and LEDs and vactrols must be correctly oriented–they are directional components. The vactrols should, in theory, have a dot that corresponds to the dot on the PCB; I know I just had mine out but I didn’t check that.
Confirm the parts list with MA and see what they say first, then you can work on getting it together.