Been playing around with the production units, and I've come across an issue that isn't really an issue.
In short, the screw used for the stabilizers in the spacebar hits the bottom when joining. In the pursuit for thinness, I completely forgot about this, and it's fully my fault.
The only "problem" that this causes is that without the top and bottom screwed together, the pieces won't be flat together. When joining the top & bottom, thanks to the properties of aluminum, they join completely fine. There are no gaps, or warping etc. I believe it's about 0.7mm that clips.
Happy to answer any questions on it that I didn't cover, and sorry I messed up