For Amazon, Michael was the only free book I had because of the reason listed above. Between all stores, Michael had 136 downloads. The majority were in Amazon.com store with Amazon.ca coming in second. Also on Halloween, other books in the series got 285 KU reads. Now, I can't say if it was because Michael was free, but it's a good chance. On November 1st I got 94 KU reads on Michael and November 3rd 79KU reads. Between November 1st and 3rd I had 5 sales for books in the Path of Angels series. As for lists on Amazon, Michael hit #1 in an LGBT list.
The breakdown by book aka TL;DR
Influence of Love––5 downloads
Michael––136 downloads and 192 KU reads*
Zadekiel––86 KU reads*
Jophiel––91 KU reads*
Gabriel––108 KU reads*
*These numbers include the week after the event since normally after a sale you get a nice boost for a few days.
Promotion of the event
My biggest hinderance to promoting the event was I had to work that day and couldn't get on a computer until after 2pm. Next year, I think I'll take the day off so I can focus solely on the event.