Nice guide, very insightful. The last part that you mentioned about acupuncture, I believe it is intended as something that lasts 'per action each turn'. Similarly, for debuffs like immobile where you activate after the standard attack of a ninja. it will carry onto next round where it stops the action of the ninja for 1 round, since it did not occur the previous round where the mystery was triggered.

So if you want to stop a position 1 ninja from moving without higher initiative, just stop him the previous round, if the opponent can't clear the debuff.