Mac users who have installed Safari 12, which is included with macOS Mojave, may have some problems when attempting to view and share and/or print their saved maps.
Actually, everything about the RTA Custom Maps still works, but the Safari 12 browser is set to block all pop-up windows by default. And the RTA Custom Maps requires pop-up windows to use the view and share tools and to print them. It used to be a simple setting to enable pop-ups, now it's 3-step process. It's still simple, it just takes a few seconds. Here are the instructions and some screenshots to give you a hand:
RTA Custom Maps Support