Hello Peeyoaquau40
Next time, simply purchase tickets from SBB: www.sbb.ch/en.
No, if the e-ticket has a QR code, then the Swiss Half Fare Card is fine to travel.
Regular point-to-point tickets and Saver Day Passes are valid on any service. Supersaver tickets are valid on the services selected during ticket purchase. You must stick to the itinerary printed on your ticket.
Kind regards,
Roland