I was playing around with the Assembling Machine and I found the following issues:

• The JEI recipe window is all sorts of broken (see image below)
• Using the "+" button to automatically place items from the recipe viewer removes the two machine upgrades in the top slots, if present. No item is placed in the input slots
• tile.techreborn.assemblingmachine.name is not localized
• [EDIT: ignore this one, I did something dumb] The craftTweaker integration doesn't allow you to specify an amount for the item output; for example, using this script makes the machine only outputs a single item

Tested on TechReborn 1.12.2 2.15.6.642, RebornCore 1.12.2 3.8.1.271, jei 1.12.2 4.9.1.175 and Forge 14.23.3.2655

I would also like to request the addition of a basic circuit board item, like the one in Gregtech that is made in the Assembling Machine (I can easily do it with other mods, but I thought it was worth asking)

YEs, JEI support for assembly machine was fixed just after release build )

I think this was fixed just after I pushed the last update. So it will be fixed in the next one.

Just to make sure you know, the second issue from the previously posted list is still there.

You mean "Using the "+" button to automatically place items from the recipe viewer removes the two machine upgrades in the top slots, if present. No item is placed in the input slots", right?

Yes.
(Sorry for the late reply, I've been away for a while)