Marjorie sent this link but it is not on the forum.
Wow, who would have thought of a solvent like benzyl alcohol being in the spot on and dissolving plastic crate or crate pan and dog getting stuck? I wonder if all the spot ons are a potential problem: I use Frontline Top Spot and most of my crates have plastic crate pans under the bedding. I too often crate the dog after application, if it is too wet to walk dog and have the stuff dry right.

http://news.vin.com/VINNews.aspx?articleId=14061#

Dog stuck in crate highlights rare risk of spot-on flea treatment

Thanks Charlotte for posting this article. I would like to add that this dog suffered for 15 hours. I urge all breeders and anyone involved in rescue to make this article part of your package. Please cross post to everyone you know.