Hi, hope to get some help to set up C1200 WDS bridge. I have read page 1 all the way thru to page 49. Especially read page 29.
I just got unifi and have changed my primary router to deco M9 (only 1 unit). Instead of buying another deco M9 to create a mesh, I thought of using the C1200 since the coverage is quite good except blindspot at the back of the house (just to cover 2 cctv, not for other usage).

The C1200 i got is 1.0.0 Build 20180403 rel.22124 (EU). I did not flash any FW yet. Using inspect sources, I managed to see WDS option in 5Ghz, enable that, survey and select my deco m9 (channel 149). I disabled DHCP, changed C1200 LAN IP to 192.168.68.2 to match m9 192.168.68.1

I did not change the IPv4 internet connection type (still the original PPPoE). I have disabled IPv6.

In Status, WDS status: Assoc
Rebooted C1200 and I tried to connect to the 2.4Ghz ssid but it cannot connect, failed to obtain IP address.

What did I do wrong? Did I miss a step? My WDS status is not showing Run.
Do I need to flash another EU FW? Or is it C1200 cannot connect to m9? I was not able to find info on how to change m9 5Ghz channel to 36-48. It does have a 44 channel but if I click Survey and choose this, WDS won't connect.

Any help is appreciated. Thank you in advanced.