Update: On firmware1.9, I managed to read stored DTC codes on my 99 3000GT VR4 ECU. I only get 9 errors, but when I use Evoscan it shows an additional 2 more errors. I'm a bit puzzled as to why this is so, I'm speculating Evoscan is including "pending DTC" with the stored DTC codes. I'll resume testing when the rain storm passes.