The part that struck me as most ridiculous about this was that the technology export was legal as long as it was "dual use". If China had just done a better job

The part that struck me as most ridiculous about this was that the technology export was legal as long as it was "dual use". If China had just done a better job of covering up their true intentions, then UTC wouldn't have broken any laws in the first place. I'll be the first to admit that I'm not an aerospace engineer. I imagine that some of the required "customizations" would have been difficult to request without revealing the true purpose of the aircraft. Still, the Chinese are pretty good at reverse-engineering, and something that does 90% of what you need has got to be a good starting point.