Just as I bought my Brompton two years ago, the Brompton announced and almost came out with their own semi-hard shell. I phoned around to many dealers, but the case was never shipped to any of them. Apparently it was too hard to design and build a case to that met their expectations, so they stopped the project.

I can't recall any problems with the cables being squeezed. Like you, I also moved the shifters as far down on the bar at they could go so that I could put Ergon grips on. That being said, I haven't checked specifically on the cables when packing, but when unpacked, I don't notice any cable damage.

As an aside, my local LBS recently suggested I put a notch into the Ergon grip to accommodate the shifter clamp so that the grip could slide down further - worked pretty well (of course, it can only go so far). (I had already trimmed the grips down a bit when I first put them on a couple of years ago.) A utility knife can cut out a small section really well.