Hi, let me make this a bit clearer (I was the one who implemented this, with Acerbic's help).
The physical version of Sweep says:
Each time before you use the action space card left of the card that has been most recently placed on a round space, you get 2 clay.
As you say, swolpoll, Lumin's
Unofficial Compendium has a note:
The action space must be Round 1-6 or 8-12.
The point that Lumin is reminding people of is that in the physical version, Sweep only procs if you use an action space
card, not the permanent action spaces (like Farm Expansion, Meeting Place etc).
The problem is that in the online implementation, this wouldn't work, because to fit on screens in a sensible way, the game is laid out differently. So spaces that are adjacent online are not necessarily adjacent in real life. (As an aside, you can see this clearly with the card Water Worker. In the physical version, you get a reed when you take an action space adjacent to Fishing. But online, the Round 4 space is not adjacent to Fishing, which is why you get the seemingly random reed on Round 4). If you implemented Sweep with exactly the same text online, it would proc much less often than the game publishers intended.
In order to keep Sweep working similarly to the physical game in spirit, the decision was taken to update Sweep for the online version. This is why the card text starts with "UPDATED":
UPDATED: Each time before you use the action space above the most recent round 1-14 action space, you get 2 <CLAY>.
So now, Sweep procs when you use
any action space that is
above the most recent action space card. If you look at the layouts of the boards online and in person, it will be clear why "above" online is spiritually similar to "to the left" in the physical game. And to keep it working on roughly the same number of action spaces, it also work on Day Laborer and Fishing in the relevant rounds.
Hopefully that clarifies the thought process about the differences between online and physical game Sweep.
One last point - I agree with Acerbic that I don't see what any of this has to do with getting points, neither the physical Sweep nor online Sweep mentions points at all.