Robert wrote:

I want to be able to play drums in my left hand while having arps blazing in my right. Problem is, even if I zone it so the drums go from C-2 to C2, and all the other sounds and arps starting C#2 to C8, the arps in the right hand are still being triggered by the left hand. Am I missing something? What's the point of having the key limits if it doesn't extend to limiting which notes trigger arpeggios?

There are two separate Note Limits. One Limits the Part from sounding (called the Part Note Limit), the other Limits the range of notes that control/trigger the Arpeggiator (called the Arp Note Limits). Having two separate parameters allows the Arp phrase to use notes outside the range of notes that trigger it, and allows you to independently restrict the region that influence controlling the Arp sorting.

You simply have to use the Arp Note Limit to restrict the range of Notes that control the right hand to the right side of the keyboard.

From the HOME screen
Press [EDIT]
Press [PART SELECT x] to select a Part
In the lower left of the screen touch "Common"
Touch "Arpeggio" > Touch "Common"

Here you can set the Arp Note Limit for this Part. Rinse and repeat as required for each (Arp controlled) Part.
Reference Manual pages 73-75

ALTERNATE METHOD:
From the HOME screen touch "Motion Control" > touch "Arpeggio"
In the upper right corner touch the "Range" option
You can now view all Parts (together), assigned to the currently select Arp, 1-8, and their respective Arp Note Limit Ranges.
Reference Manual pages 35-37