$120 for adult and $60 for kid between 1.1M to 1.4M, Kid below 1.1M is free.
Elderly between 65 - 69, $60 and free of charge above aged 70!
Hope it helps! You can check out the web link for details. You can print out the $10 discount coupon from their website, but only valid till Nov 2!
I don't know about the bus as we went last time by 深西特快過境巴士 and it stopped right in front of the park! We departed from Kowloon Tong and it took about 1 hour 15 minutes to get there, very convinent! The charge is $40 per head, both for adult and kid. Honestly the local buses are too crowdy and don't look too safe for me if I go with kids. Rather take the MTR in Shenzhen!