This is exactly what I do with the Plank dock: Xfce Panel on the left side (as per the default), and Plank on the bottom.Yes, Cairo dock can exist with teh standard XFCE docks (Thats how I run - xfce4 on the side, and Cario on the bottom.)
Nope.I assume the Plank dock replaced the XFCE dock.
I did nothing to the Xfce Panel (what you refer to as a "dock"). I just left it in the default position (left-hand side of the screen), and added the Plank dock, positioned on the bottom.
Sounds like you can do the same with Cairo.
And, heed @CharlesV :
Play with the options (responsibly; i.e., back-up)And using MX Tweak, you have the ability to backup ALL of your panels too. (If you want to experiment and NOT loose your panel settings. but THIS is what a VM is for :-) )

