Pattern Workings are lasting Pattern effects. Shadow Paths are a kind of Working. A Blood Curse is another. The 'shadows lie for you' effect is a minor Working. (The word "construct" has too much baggage in the system.) What Random did to the Adept was a very complex Working.

Fiona, Merlin and the other family wizards use Workings to protect their magics. That is, they lay a strong, lasting Probability Working to keep anyone from doing to their strongholds or gadgets what Fiona taught you to do to those of ordinary Sorcerers. (Flora used the same techniques to protect her technology in Shadow Earth.) Breaking through or getting around a Working is a matter of Psyche, Pattern mastery, effort and time.

Logrus Masters protect their holdings and stuff with Logrus Workings but they've had almost zero experience with guarding against Pattern. The last major conflict with Amber, pre-Patternfall, was a long time ago and the redheads were very careful to study Logrus defenses while revealing as little as possible about their own capabilities. Hence the Adept's weakness versus Brand; Fiona backed by Random and the Jewel could simply overwhelm him.

The Adept and his people were slaughtered and unable to pass on whatever they'd learned but the Archivists were able to watch Brand knowing what he was about to do (when he took down the Thelbane Palace defenses), and the Chanicuts learned whatever they could from being on the receiving end, unprepared. The virgin field is compromised. (And Sawall, in the person of Vramin, has more experience with Pattern than any other Chaos lord.) Vramin says that the Archivists and Chanicut are trading some of their info but keeping the juiciest bits for themselves.

So what sort of Workings can you do? Pretty much the things you do normally but make them last with a lot of extra effort and/or time. For real mastery of a class of Working, like Shadow Paths, spend points. You can be sure that Fiona, Brand and Llewella have points in Pattern Wards, for instance.

Items you've spent points on automatically have defensive Workings on them. It would be hard to mess with Mykal's sword or Archimedes' ship with Pattern. Or Logrus, as you become more familiar with it. Or Trump.