Are we allowing enough time to get to next train?

Sharon, The transfer times you've listed are very reasonable, and you shouldn't have any trouble with any of them. Once you've tried it a couple of times, you'll get used to the method for transferring very quickly. I can't remember the layout of the stations at Sestri Levante and Genova Piazza Principe, but transferring will likely involve going from your arrival platform, down stairs to a tunnel and then up stairs to your departure platform (this is why packing light is a benefit). The schedule boards will show which Binario (platform/track no.) your train will be departing from. The train numbers shown on your tickets provide a good way to double-check the track number. Two of the trains you'll be using will be Regionale, so DON'T forget to validate your tickets prior to boarding the train on the day of travel. Finally, there appears to be another departure from Manarola at the same time, with a shorter travel time, arriving in Varenna about 30M before the one. It has one additional change in Lecco. The trip from Milano Centrale to Varenna is 1H:03M. Just before arrival, you'll go through a tunnel. BE READY to disembark promptly, as the train only stops for about a minute. Depending on which hotel you're using in Varenna, you should be able to walk from the station (it's mostly downhill). Happy travels!

You'll actually go through several tunnels on the trip from Milan to Varenna. Make a note of what the stop is BEFORE Varenna, so when you see that station, you can be ready to get off quickly the next time the train stops. It only stops for a minute or two.

Here is a photo of Genoa PP station. Not very spread out. Max 150 ft between platforms.
http://en.wikipedia.org/wiki/File:Genova_Piazza_Principe_railway_station.JPG

Ken, Thank you for the reassurance. Unfortunatley, we will be "getting the hang of it" on this day. I was concerned because I felt like the station in Genoa might be too spread out to get from one train to another in 11 minutes, but we will be ready to move fast! I did see that other train from Milan via Lecco and dismissed it thinking it would be a hassle to change trains AGAIN. Maybe not? Great tip about disembarking in Varenna! Thank,
Sharon

Thank you for the pic and the tunnel tips...everyone is so helpful. Makes me not stress about it!

We arrived in Italy on Monday. Our first day was getting our train legs up to speed. Last trip we drove, so my advice is from a Newby train traveler.
First, we wasted times at the ticket machines in Florence. Credit, debit cards do NOT work (apparently in my jet lag state I forgot.) Not all machines take cash but only credit card options. By the time we realized this we'd missed the train we we attempting to catch. There's a red picture of cash next to the various credit cards across the top of the machine. Put in your final destination, Varenna, and all tickets will print. Note that some tickets have 1 ticket for two travelers and other faster trains might have 1 ticket per person. Remember to validate before each train. Have either a printout of potential train itineraries for that day. If you flight is late, know your options. Know how to spell destinations in Italian. The train numbers are very helpful in confirming which track you are on. This saved us, we had one connection that was 4 minutes due to the first train arriving late. On the trenitalia web site click on the info button- that shows all the stops- very helpful to know the stop before yours so you can start moving you and luggage toward door when train starts slowing for your stop. And don't be afraid to ask others if you are getting on the right train. A couple trains they announced stops in Italian and others you have to look for the sign outside the windows. Everyone was very helpful. One older lady made sure we got off at the right stop.

Karen, Where you using a swipe credit card or were you using the Chip and Pin technology credit card on the train kiosks?