the wizard kits only operate at 100% throttle so no, it wouldnt cause issues with the VDC. you should avoide hitting the limiter at the best of times, on nitrous you must not hit the limiter at WOT with the nitrous injecting as it will continue to inject whilst the fuel will be cut. not good.
my advice would be to switch the VDC off when running nitrous
ps. i run the wizards streetblast 150i kit on my MG and it is superb, very smooth delivery and crazy powerful - brilliant fun. im only running a 50hp shot