KDP has book building tools like comic creator which created .mobi or Kindle create that creates .kpf

Has anyone used Ingram's book building tool? I would have preferred an offline version to test how it works before creating an account. I have tried searching video's but only come across examples for reflowable e-books.
For some of my books, I need to specifically know whether it can upload .pdf files and convert it to either their own format, or to .epub.
This will be for fixed layout books or children's books. I dread having to go the Calibre route again...

Thank you