Read this thread by Silverfox, follow the instructions and you will have no worries.
http://www.cigarasylum.com/vb/showth...ience+freezing
I have used it on my entire collection because of increasing temperatures in the summer in my humi, and fortunately have never had an outbreak.
As far as the RH at 61% and the temp at 71 F, I wouldn't worry about that. I store my entire collection at 65%, and have heard of some storing them at around 60% or even as low as the high 50%s (less than 60% would make me a little nervous though).
Hope it helps.