on stationary birds i use center spot focus then go to animal eye it normally locks on the bire then the eye. buttons set AF on as center spot, * as eye. if it does not lock on i switch from spot to eye. sometimes when there is lots of other high contrast or berries this takes a few times. The AF can be tricked and is not perfect but there is nothing else that comes close. you can use manual but most of the time the AF locks on faster then i can and is more accurate. I have just learned to work with the quarks of the system. There is nothing else out there that is better or faster.
OT I know, but I set up my R5 this way, and liked it enough that I then tried setting up my RP the same way (well, it doesn't do ANIMAL eye focus, but it does do people). Basically, the * doesn't do anything at all on the RP. On the R5 it will enable eye focus while held down; you effectively switch modes depending on which button you are pressing. But the RP just ignores the * press.