The Master Page should be stupid simple. Just open the Topic List pod, select all the topics, then right-click and nominate the Master Page of choice.
As for the URL bit, I'm not sure I've ever done this. Which is odd, because I've used the product for 20+ years! I'm guessing that what you will need to do is use the Multiple File Find and Replace to hunt the instanced down and change them.
In thinking about this, it occurs to me that you might help yourself out by electing to replace the URL instances with one or more variables. That way if you do ever need to change them down the road, it would be much easier as you would just update the variable(s).
Thanks, Rick! How is it I never noticed the ability to select folders in the topic list?!? I always had it on the default "all files"... I had been picking through topics and applying in batches. Luckily the ones I *don't* want to apply the master sheet to are in a folder, "use case steps". Many thanks!
As far as replacing with variables... well - there is another topic for your next class! Never have done that
Greatly appreciate the fast response!!!