Mr.Thomas,
Take No.81 bus from the railway station to Longmen Grottos. From Longmen Grottos to Shaolin Temple, you may take tourist bus at Longmen Grottos. The bus leaves at 10:00, 11:00, 13:30 and 14:30. It contains the entrance fee of Shaolin Temple, bus fare, tour guide service and insurance etc. The price might be expensive. I have heard that it is around CNY400.

As for Kungfu show, I have no idea. The info reveals that it is performed at 15:00 or 17:00. But another news says it is performed every hour and lasts for half an hour. It takes around 1 hour from Shaolin Temple to Luoyang Railway Station.

For G train ticket, better reserve it in advance. See, it is travel peak time now.