Thanks everyone for your help with the plan. We have decided to leave towards end of August and spend the first week in Fussen area with a rental car. Then we will travel by train to Salzburg, Vienna and Prague.
Have not yet decided on the best train route but thinking of di=oing:
Fussen- Salzburg; Salzburg-Vienna; Vienna-Prague; and Prague-Munich from where we return to Canada.
Will report on our experience when we get back. Getting excited already.