From Hong Kong to Xuchang: You can take Kowloon to Beijing train T98A which passes through Zhengzhou. Then, you can change a train or bus to Xuchang which is only a half hour from Zhengzhou. Or you can flight to Zhengzhou from Hong Kong. Zhengzhou Airport has shuttle buses to Xuchang, departing at 12am and 4:30pm. You can also choose to take taxi, for it is only 50 km (about 60 rmb at daytime) from Zhengzhou Airport to Xuchang. Good Luck!