Sure, there is a big learning curve to the new version. But don't blame the developer for that! Firefox Quantum requires WebExtensions, which required a rewrite of NoScript, and major changes to how it works.

Aside from the UI (user interface) being a bit confusing, it just works (it even remembers your old site preferences!). That's what you want it to do, right?

Before adding it, take a look at the description, and go to the link shown there. It explains the UI and how it works. Click the "S" once for temporarily trusted, twice for permanently trusted.

For security software, the most important thing is that it functions properly. From everything I have seen, the new version does exactly that. I'm not going to knock off a star (or 4, like some people?!?!?) for a change in the UI; I chalk that up to Quantum (and Firefox's mistake of auto-upgrading to a major new version without asking).