I can't find a "MFi Licensing Handbook" in https://mfi.apple.com/. Please help me to get the handbook.
After you've logged into the portal, choose "Content Center-> Content" from the tab bar at the top of the page. That will leads to the section of the site where you can download all of our specifications, however, the MFI licensing handbook is always the very first link in that list. You'll also find all of the Find My specifications on that page.
In my MFi account, it has a representative, can I ask him about CSR and testing token?
They may not be able to answer your technical questions but, yes, they should be able to help you get to the right information.
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Kevin Elliott
DTS Engineer, CoreOS/Hardware