Josty

Great protection Motrax received then, if a chapter 1 party could kill him....

More seriously, isn't Motrax supposed to give you some clues / info in chapter 4?

Nope, in A1, the potion is also called knowledge brew (given 5 skill points).

Is that bad memory Alorael, or just another version 1.0 reply?

In A1, the flaming sword does pretty well, and you get it fairly early in the game. Surely, demonslayer is better against demons, but not against other enemies. Make sure to collect smite (a halberd or pike) before doing the giants quest, as the additional damage to giants is good. Otherwise, the best halberd is the blessed halberd. Early in the game, stick with a fine slith spear.

Does it holds for all avernum games that crossbows do twice as much damage as normal bows? That holds fur my current A1 game, even though my crossbow-wielder is less skilled than the PC with the normal bow?

yep, that's a good guess!