Latest SW release questions

[cdeggz]

A few questions regarding the last SW update:

Latest update includes "Adds warning message when servo slips occur"
I was flying with this SW build for the first time last night with AP in heading mode. I adjusted the heading 30 degrees to the right and got this error, and the plane quickly rolled to the left. What exactly is a servo slip? (Servo not being able to hold/reach the requested position?). For what it is worth the AP was always able to follow the heading bug before the SW release.

Latest update includes "Adds SV-Autopilot altitude filter modes"
What is this exactly?

Lastly, is there a way to filter ADS-B traffic by altitude? I don't really need to see traffic in the flight levels as I come in for a landing.

Thanks in advance!