Booking a trip from Munich to Murren and am going through the checkout process on bahn.de and no matter which time I select or seating preferences chosen, I always get the message "No diagram available" for the first leg of the trip. Will I be able to reserve seats at a later time? Bahn screenshot here
The "No diagram available" message doesn't mean you can't reserve seats. It just means they can't display a map of where your reserved seat is located. It's a very common message for IC trains. After you reserve your seats you can look up the exact location at this site: http://tinyurl.com/bleuxbx
Exactly! It means DB system will automatically reserve you seats based on your stated preferences (windows/aisle, compartment/open floor, silence area etc.)