4 day saver pass or 50% discount pass

Who said traveling by rail in Europe is easy - guess the hardest part is figuring out what pass to use?

My wife (age 57) and I (63) will traveling from Zurich to venice in Sept. Trying to compare the 2nd class Saver & Discount Passes. Prices are USD for the two of us.

Date . . . . . . . . . . . . .50% / 4 day Saver
9/12 Pass prices . . . . 222 / 474
9/12 Zurich to Lucerne . 29 / 0
9/13 Mt Rigi . . . . . . . .111 / 0
9/14 Lucerne-Engelberg R/T 34 / 0
9/15 Wilhelm Tell Express . . 82 / 82
expires
9/16 San Salvatore . . . . . 30 / 59 I assume this qualifies for 50% discount?
9/17 Bus Lugano to Menaggio ? ? Don't know the price? Pass discount?
9/19 Buses around Lake Como
9/20 Train to Milano Centrale - Ferrovie Nord
9/20 Train to Venice - Trenitalia

Questions: Do the above prices look correct? (USD for two)
Is the San Salvatore funicular discounted 50%?
Price of bus trips to Menaggio & around Lake Como? Discount deals available?

Thank you for your assistance!!!