From Zürich HB, there is the S8 ( 34 minutes to arrive ), S2 ( 26 minutes to arrive ) and the Inter Regio heading to Chur departing every 12 minutes past the hour arriving in 20 minutes.
Venue is beside the Bahnhof as well as no more than 2 mins walk on the other side.
We were there at 2-4pm and the crowds are definitely manageable. No waiting time for rides at all. So anyone wanting to go today might want to go for early afternoon to miss the crowds.