It doesn't matter. From experience, the more detective work and over analyzing which you (needlessly) take upon yourself, the less you get laid! Yes, the whole thing smacks of stalkerish behavior and if I notice that someone just keeps looking at me without responding to my email, or in general just gives me the creeps by looking and not acting, I would most definitely block her and move on!

"I've noticed that if you mark a lady as one of your favorites, you can go to "interests" and click favorites and it shows how long ago that they were "active" in hours."

I am usually looking on my iPhone, so maybe it's different, but mine tells me number of hours SINCE they were last active... not how long they were active for.  

Also, I do think they need click on your profile for it to be "viewed". It might not be a big deal. Usually when I am prospecting, I will put in search parameters and favorite ANY/ALL girls that I think are hot or I like there profile. From there, I whittle down from my favorites who I will message. This seems to work well bc once i fave them, they will know and usually check my profile and/or maybe message me before I have to message them... seems to speed things up with some. That being said, once I fave someone, I may go back and view them again a number of times before deciding to reach out to them or if I like there pics, etc...

Bottom line... if you like her profile, message her and see if she responds. If no, block her... it's that simple.