Thanks for your message. It might be better to ask in the French-English vocabulary forum (this forum is for reporting errors or suggesting improvements to the dictionary; the vocabulary forums are for asking questions about specific translations or terms). However, as I can't see a sense that would cover this, I will pass this to our FR base to see if anything needs adding.
Meanwhile, I'd probably say something like 'This blasted nail keeps snagging/catching on stuff'. I definitely wouldn't use 'snagging' like an adjective. I think ain'ttranslationfun?'s suggestion isn't quite right, as a hangnail is a bit of skin that's torn loose around the nail, and I think you are talking about the actual nail. Like I say though, the place for this discussion is more properly the vocab forum, so if you'd like to post the question here you will probably get a better variety of answers.
@Lacuzon - I can't see a sense that would fit for this. Something to add?