I'll answer what I'm able to here. Anything else I either missed or need to take some time to track down answers.
Vehicles mention that if the modified DV does not exceed the Armor, the attack is a bust. Should that include the AP value for the armor value comparison? i.e. is this a rulechange in comparison to 4e, or an errata-required?
AP always applies before the vehicle armor (or Hardened Armor power) threshold is checked.
Did I miss something? is it an error? or is it the way it is intended to work and in that case I am curious about the explanation (be it in-game or game play reason, I can understand both)
Low-Force spirits are less useful and weaker in the physical world than those with higher Force. Their connection to the physical plane is more fragile than that of a more robust spirit. They're also kinda weak-minded (Mental attributes of 1 and all).
If you'd like to change the limit on the summoning of your Force 1 spirit, you can either use Edge or reagents for the summoning.
Firing modes p178:
SS vs SA: Why firing one bullet per action phase in SA mode generates some recoil while firing one bullet per action phase in CC mode does not? My feeling is that SS weapons are slower to chamber the next round, making them unable to perform semi-automatic burst, but why does it prevent recoil?
Partly because you do have a bit of extra time to recover from the single point of recoil it generates, and partly because we thought SS weapon users deserved a break.
Is it how surprise is intended to work, or shall the surprised character lose his next action phase (i.e. do nothing during his action phase and lose 10 initiative)?
Yes. Really, really
fast people still have the possibility of recovering from a surprise fast enough to take action first.
Do Counterspelling Dicepool Modifiers count on each Counterspelling, or only once on the Counterspelling+Modifiers pool that you then drain from whenever you spell-defend?
Would you please rephrase this question? I'm not sure what you're asking, but spell defense is on p. 294 if that's helpful at all.
I can'T see anywhere in the book if you fall unconsciouss once your stun monitor is filled. Has this consequence been removed?
Nope, it's still in there, just not as prominently as it probably should be. Page 100.
I'm still working on the other questions.