I'm in a bit of a rush because I slept later than I intended, so I'm not going to be quoting page numbers.
Q1 No, only certain armors can be integrations.
Q2 Yes, for the SF armors. As I have run a SF/Fantasy combo, I would rule that certain armors, such as maille cannot have either enhancement.
Your example is missing some information.
Ablative DB applies only to damage from Blaster, Laser, and Plasma, though I personally would allow Heat as well, and only applies to the total DB if that is the kind of damage received. Likewise, Kinetic DB only applies to projectile damage, and thus is only part of the total DB when the damage comes from a projectile source. Remember also that when kinetically enhanced armor takes the appropriate hit it hard locks the wearer's facing for one round.
Q3 and Q4. This is a hard call. Martial Law would say to take the elements of the enhancement and multiply them by the enhancement's IV, then add adjusted parameters together before applying them to the base armor. However, SF seems to want to keep it simpler, at least in terms of DB and Armor Penalty. So consider this an "I don't know" answer.