Hi, my friends and I are new to this game and till now we have played using LOS rules but without applying the part that says "figures block line of sight". Now we are quite confident with the game and we would like introduce this rule, also because the game is extremely unbalanced without it. The problem is that not everyone agree with my reading of this rule so i would like some explanation from you.
 

1- Do friendly figures block line of sight?
2- Blast says “… A space is only affected by the Blast attack if it has line of sight to the target space…”.
So, figures may block the blast's espansion by blocking line of sight to squares behind them, even if the radius of the blast would permit to reach other figures, or the spaces in the radius of the explosion have to be checked without considering figures?
So, in the example of Blast (page 22), in the example to the right: if instead of the 2 squares occupied by rubble would have been 2 figures (heroes or monsters) the beastman on the left-high corner would have been hit by the blast attack?

Thank you

1 - For purposes of targeting a space for an attack, all figures block line of sight, be it friendly, enemy or other (like villagers in RtL).

(For purposes of spawning, a figure never blocks line of sight, but I guess that´s not what you meant).

The only exception for targeting attacks are figures that are not in LoS themselves - these do not block LoS even if they are "in the way" (this was introduced to resolve some special constellations - it sounds weird at first, but it does prevent weird situations while creating a few others) - see FAQ.

2 - Blast (and Sweep) checks for affected spaces ignoring all figures, so a figure cannot "hide" behind another to be safe from such attacks. Only obstacles that block movement would block such an attack effect.

Thank you for the answers.

You have confirmed my interpretation.