New Orbi RBK853 setup; multiple issues after setting up

I just received my Orbi 853 (AX6000; 3-pack) from Netgear and set it up this morning in my environment.  SFH, 3 floors, ~4000+ sq. ft., about 48 clients in mixed 802.11ax (1), ac, an in both 2.4 and 5 GHz.  Using a single SSID.  Firmware was automatically updated to the latest version: V3.2.15.25_1.3.15.  

The initial setup (just the router) went fine but then became unstable.

Some symptoms and the changes I made:

1. I noticed most of my IP cameras (Foscam, 2.4 GHz) were going offline in Blue Iris every few seconds.  I think the issue was the default RTS/CTS and after changing it to 500, it seemed to have stabilized and the cameras remained online.  What should I set them at?  500?  Saw another thread that said it should be at 2347?

2. Wired backhaul; I can't seem to get a stable wired backhual for my satellites going.  Out of the two satellites, only one would connect and remain connected via wired backhaul but the second would't, no matter what I tried (reboot, replace patch cable, etc.).  I saw another thread that mentioned a "daisy chain" setting in the Advanced Settings/Wireless tab but I don't see that option on my firmware.  Is wired backhaul broken in this firmware?

3. Placement: SFH, 3 floors.  The two satellites are each placed in a bedroom wall at the opposite ends or sides of the house on the 2nd floor.  The main router is in the basement level which is centrally situated in the middle of the house.  Every room has an ethernet wired jack.

4. Anybody here using Circle Plus (the external device) with the Orbi 853?  Should the Circle Plus be set up in regular or compatibility mode?  I currently have the Circle Plus disconnected/shut off while I'm troubleshooting these issues.  Currently, I have just the single router running and the two satellites disconnected/removed from the network and everything seems stable so far, but obviously would want to connect the two satellites.

Thanks,
David