As stated in the article, the artist, Tashi Norbu has added elements of political nature in some of his painting. So, it is not accurate when Tashi Norbu says he's just an apolitical artist. Since, the government cannot be sure of what the end result of the live painting event, they are just playing it safe and avoid any potential international incident. If Tashi Norbu's art has always been apolitical, then I don't think there would have been any issue for the event. So long as the Dalai Lama and the CTA refuses to a dialogue, then incidences like this will continue to happen.
As mentioned by ShugdenProtector, Tibetan leaders should
1) stop dividing them - Shugden and non-Shugden, Rangzen and non-Rangzen
2) Stop condemning China if you want dialogue. Who on earth would want to talk to anyone who keeps barking at them?
3) Unite all Tibetans
4) advice your own people to be kind to one another not curse one another due to religious differences!
5) Stop trying to get the West to help you, they have never helped you, it's been over 50years and where are you at now? It's time to seriously wake up people!