That's probably a healthy approach, especially if you're feeling emotional about the situation right now. There's definitely not a big rush. Keep in mind that

That's probably a healthy approach, especially if you're feeling emotional about the situation right now. There's definitely not a big rush. Keep in mind that it is very unlikely they'll try to litigate against you——they're the ones who have the most to lose. Not only could they potentially have violated your copyright, but they also risk significant perceived damage (many VCs won't touch a startup in litigation with a 10 foot pole).