If my ship is on a dust cloud, and the yellow dot for LOS is in the cloud but the front of the ship protrudes off the cloud, are all my attacks lost for that entire arc or not?

FAQ page 5:

OBSTRUCTED

Q: While a ship is overlapping an obstacle and the attacking hull zone’s traced line of sight does not pass over a visible portion of that obstacle, or another obstacle or ship, is that attack obstructed?

A: No

Although not specific to dust clouds, it should be stated that this essentially works as a ruling - if you're not obstructed, its because your LOS was not traced over the obstacle.

In which case, you did not trace LOS over the Dust Cloud, and it does not block your attack.

So For LOS the line is placed from yellow dot to yellow dot... but only 'traced' from hull zone to hull zone, along the line between yellow dots?

Just now, Rettere said:

So For LOS the line is placed from yellow dot to yellow dot... but only 'traced' from hull zone to hull zone, along the line between yellow dots?

Basically.

If you can't see the Obstacle because the ship is in the way, you can only "Guess" where it is, rather than measure - and Guessing isn't good enough.

Thanks!