The overall effect of all the Comey shenanigans have still been very harmful to Clinton.
1) The dominating story for the last week and a half of the election was e-mails, which reinforce the (stupid) narrative that Clinton is currupt.
2) The focus on e-mails and subsequent tightening of polls allowed for Donald Trump to lay low. Does anyone believe that Donald Trump would not have thrown huge tantrums had Clinton spent this last week still leading decisively in every important swing state?
Clinton was dropping, somewhat inexplicably, in the week of the Friday Comey revelations, much like Obama did in 2012. Comey did two things, I believe. 1. It prolonged a slide that was already in progress. 2. (and probably more damaging) It hurt the personal ratings that she recovered during the DNC, then the debates, which probably had a lingering effect with the remaining undecideds.
So long story short, I don't think the specific Comeygate nonsense hurt her TERRIBLY, but it did have an impact.