I don't know what you mean by training with him, I attended his classes in Denmark and Sweden for many years, and began teaching on his request.
I also published the only Magazine on Tai Chi in Denmark with a fellow student. This Magazine stopped being printed in 1999 and became an Internet Magazine instead : www.taichinyt.dk
This Magazine Master Tung was very pleased with.
I also wrote the only book ever published in Danish on the Tung Tai Chi, with Master Tung's approval.
I do not participate in his classes any more, but never the less I deeply respect him and his roots.