1) I seem to remember the rule for "trading down" a gear pick to get two picks of a Caliber 2 less in the same category was in the 2.0 first printing, but I can't find it in the second printing (SP). The option is, however, listed at the appropriate Calibers on tables 4.9 Electronics Gear, 4.10 Gadgets, 4.12 Security Picks, and 4.15 Tradecraft Gear. Can you still "trade down" Resource, Vehicle, and Weapons Picks?
Alternately, a character may trade in any number of gear picks to gain lower-Caliber items and upgrades in that category. For each pick sacrificed, the character gains 1 item whose Caliber is up to 1 less than the mission's current Caliber + 1 appropriate upgrade (if sacrificing an Caliber II or III pick) or 2 appropriate upgrades (if sacrificing an Caliber IV or V pick).
Table 4.13 Armor has, at every Caliber above I, the option to get a pick 1 less than that Caliber with 2 upgrades. Is that correct? (It makes perfect sense to me, as armor pretty much runs on upgrades, and I'll go by the book at my table.)