I stick to http://paizo.com/pathfinderRPG/prd/ rather than that other place for the most part.
Yes, fire it at a square if you like - in the absence of something more concrete, I usually as for AC 5 to hit for that kind of thing.
|Smokestick: This alchemically treated wooden stick instantly creates thick, opaque smoke when burned. The smoke fills a 10-foot cube (treat the effect as a fog cloud spell, except that a moderate or stronger wind dissipates the smoke in 1 round). The stick is consumed after 1 round, and the smoke dissipates naturally after 1 minute.|