Ah, you need to generate a nicnt file first before you can add them to Kontakt. Just open the folders of the library that you successfully added and you'll find a file with nicnt extension in the folder. Not all library comes with it, some you have to manually generate it yourself.

There are a lot of threads here explaining about all the steps needed, good thing is since you have Bobdule's Kontakt installed you probably already have the tools needed. I wish I could explain it in this one post, but it would take an hour of typing to explain all the steps and few important things to understand. Reading and understand all of them will take less than 1 hour though, so in the spirit of efficiency I suggest you use the search function in this forum and find the aforementioned threads for steps to manual generate nicnt file for Kontakt library (Non-NKS Partner) that doesn't have it. You'll find that you can customize a whole lot of other things to suit your workflow as well and I promise you it will be super fun. Good luck.