Look here for answers to any rules or crunch questions that come up often enough to require public clarification.

Background Skills, Feats, and Traits
Because we employ background skills, any feat or trait that offers a generic bonus to all Craft checks also grants that bonus on Artistry checks, and feats or traits that add a bonus to all Knowledge checks also grant that bonus to Lore checks. Likewise, for feats or traits which allow a player to choose any Craft or Knowledge skill to receive a numerical bonus, Artistry or Lore (respectively) may be selected, instead. Feats and traits that improve a specific, named Craft or Knowledge skill still only apply to that particular skill, not to Artistry or Lore.

Familiars
After consulting with official Paizo personnel, including top designers, we've determined that—regardless of how the text reads—familiars do gain feats and ability score increases like any other character, based on their Hit Dice as determined by the master's spellcaster level. Be sure to take advantage of upgrading your familiar! Feats (like Toughness) can make a huge difference!

Lyre of Building
The introduction and integration of the kingdom building rules left a few holes here and there that have yet to be patched (to the knowledge of the administrative staff) with official rulings by Pathfinder developers.

One of these, importantly, is the lyre of building, a powerful magic item with the potential to create huge effects in this type of game. Based on extensive discussion, this is how we've determined that item to operate:
  1. Each 1/2 hour played counts as 300 Labor Capital toward the construction of a room or building (equivalent to 100 humans laboring for 3 days, as described). If the total time played brings the total Labor created by the lyre to a multiple of the base Labor cost of the room or building, then final construction time is reduced by one increment, as described in the downtime rules: "You may divide the Time price for a room by 2, 3, or 4 by spending 2, 3, or 4 times its Labor price."

    As an easy example, say a building costs 100 Labor Capital to produce; since playing the lyre for 1/2 hour generates 300 Labor, using it successfully to assist with the construction of this building would mean you are spending 3 times its Labor price (assuming you aren't also spending actual Labor Capital, as well). Thus, the construction time of the building would be divided by 3.

  2. Construction time is waived (replaced by the time subsumed in the item's activation/associated Perform check)

  3. The goods Capital portion of the construction must still be provided on-site; the lyre does not create raw materials, only labor.

  4. The virtual "Labor Capital" produced by the lyre does not count toward how much Capital can be spent per day, based on community/settlement size.

Spellcasting vs. (Sp)
Regardless of any ruling by the Paizo design team or of any conflicting opinions on the matter, spell-like abilities never qualify any creature or character for any feat, prestige class, or other feature whose text necessitates spellcasting capability. That is, spell-like abilities are not spells, and so a requisite that a character must be able to "cast spells" or must have "caster level X," etc., in order to qualify is not met by the possession of spell-like abilities.