Thanks for the response - great deal and yes the early bird doth get the proverbial worm as those type tickets are sold in very limited numbers

If you buy a ticket, as we did, from Trieste to Venice that was good for any train, you need to stamp it at the station before getting on.>

this is only possible now on regional trains - all other trains will have a seat reservation with the ticket I think. So yes a good tip to prevent a surprise fine!

Many thanks for all your replies. We've decided to scrap Sicily and Malta this time. Too complicated and long train voyage. We'll just spend extra time in places as far south as the Amalfi Coast. Next time Sicily and Malta perhaps. Good tip on the train. I hope we don't muck it up and get fined. Cheers