About ADP2389 Accuracy and minus current

Hi, 

I would like to use ADP2389.

So, I have two questions.

#1  When RILIM = 59 kΩ, the peak current is stated as 15 ~ 18.6 A. (From data sheet)
    Is this variation in output peak current equivalent (about ± 10.7%) even if the resistance value is changed?
       Are there any indicators?

#2   Is there any problem if a negative current flows in the FET of ADP 2389?

Best Regards,

Yuya