Posted this one over on the Shadowrun boards as potential errata, but was suggested to add to FAQ instead, so posting here (even though I think it's way off and wrong).
pg. 251, Threading, second paragraph, last line, reads "You can choose a Level up to three times your Resonance rating." I'm thinking this needs to be two times your Resonance rating." for one, going up to 3 times is insta-glib on yourself. Also, it flies in the face of other set traditions in the magic and stuff. Magic spells can only have a Level up to Magic x 2, Summoning Spirits is Magic x 2. Other limits (when multiplied) are x 2. Heck, even later on on page 254, Compiling a Sprite has a level limit of Resonance x 2. So, I'm thinking a Threading Level max of Resonance x 3 is both error and overkill, to be honest.