I certainly don't have a problem with her paying for the dossier, nor do I have a problem with her distributing it, although I would give 2:1 odds that not a single scandalous allegation in it is true.
What I would have a problem with, and I'll admit this is educated conjecture on my part, is the Hillary campaign using the dossier in a sneaky way so as to tempt the national security agencies to investigate Trump and his colleagues. Now you might ask (justifiably IMHO), "how could the FBI/CIA/NSA be so dumb as to fall for such a baseless pile of garbage?" My answer would be, "well, these people aren't rocket scientists, and they probably are the kind of people to jump at the excuse to conduct an investigation of a political campaign."
My spidey senses have been telling me for a long time that this was a baseless investigation that was instigated by the Clinton campaign, with the less then enthusiastic (but still material) support of the Obama administration. It's probably true that if Trump wasn't such an idiot, it wouldn't have gotten much traction (and certainly not a special prosecutor on Trump's ass), but the fact is, it's still a garbage investigation.