A few questions

[Mobhack]

1) Weapons lower down the priority order may not fire - depends on supression and also on the firers experience and also damage to the unit (casualties or "*" hits to AFV) as well as warhead size. Also depends on unit leader ability, or if they have a senior HQ within 3 hexes to "coach" them.

Also - the enemy reaction may break the "chain of fire" - so weapons that had a chance this shot may lose it (e.g. the target pulled back or hit the dirt, or somebody fired back adding "S" to the firer in the firefight).

(So - if I have a depleted & supressed section and really need to be sure of the 1 PIAT shot in slot 4 - I tend to use the "W" key method to fire just that slot to be absolutely sure.)

2) Totally destroyed units will start as a new default training and experience rating unit for the time frame. A vehicle with surviving crew is not destroyed - it will be badly damaged.
Destroyed leaders will result in the next unit in the formation becoming the new leader (usually).

3) A badly damaged unit (50% damage or worse) - will tend not to increase in experience and may suffer a set-back of a few points, just like if you changed the unit type in the fix/repair screen.