You're right. I initially assumed that the CVT and diff shared fluid, but it definitely does not. Looking further, filling is very similar to a manual transmission. There is one drain plug and one fill plug. No dipstick.
Fill to bottom of fill hole. Warm fluid to 95-113F while cycling through PRND with engine idling to circulate fluid. Add fluid if necessary to maintain fluid level. Replace fill plug (and new gasket) when done.
I see no mention in the service manual of a computer reset or calibration after fluid replacement, but perhaps I'm just missing it.