Printable output of a web-driven gallery is something near to "mission impossible": the www was never built with printing in mind. There are projects that focus on doinbg exactly what you're up to: coming up with a layout that will allow you to print HTML-driven pages. However, the print pages will not be related (design-wise) to the design of your www pages.
That's why I'd say that your second request is turned down, because of two reasons: first, because it't technically nearly impossible. Second: because we have a strict "one issue per thread" policy that you agreed to respect when signing up. That policy applies especially to the feature requests board.
Enabling users to print locally by modifications applied to coppermine's code is (as I suggested above) technically nearly impossible. What you could technically do is export parts of a coppermine-driven gallery and send that content somewhere for purposes of downloading. The downloader could be the end user with desktop software that will do something clever with the download (i.e. generate printing pages) or a picture service like Snapfish e.a.
This being said, you'd have to come up with a desktop app, which is something the coppermine dev team members are not familiar with. So, if you need the printing feature badly, you'll have to team up with others (like Snapfish or other printing services) I'm afraid.
Some food for thought:
Joachim
P.S. We're not affiliated with Snapfish. I just mentioned them as they are the most important web printing service these days, from a global perspective. There have been others (like Pixaco) who have been bought or who have quit one way or the other. There are local services available as well, but we're talking about a global solution, right?