The num pad configuration toggles on and off like the old IBM keyboards with num pad. When the num lock is on, typing on the num pad keys produces numbers.
When the num lock is off, typing on the keys activates the labeled other function (Ins/Del/cursor up/etc.).
A key on the keyboard will be for Num Lock so that you can switch between num lock on and num lock off.
You can also configure a function key to activate the Ins/Del functions – this is what I do on my F77. So Fn+ Num Pad 7 = Home, Fn+Num Pad 9=Page Up. I configure the right ctrl key to be Fn but any non-modifier key can be a function key (the shift cannot be a function key because it is a modifier key).
Everyone ordering an F62/F77 (besides those ordering the “bring your own keys” option) gets a full key set: both the num lock and page up/home/end/etc. keys so that you can switch in the future.