@Ajcvzj 

You can try Client Mode so no WAN IP required, the devices will be able to obtain IP from the main router directly.

I think the issue could be on CPE IP address. If you choose router mode, the CPE must use a different IP subnet from your main router.

  @Somnus Hi, thanks for your answer, but it doen't work, actually my initial configuration was in Client mode (and it worked OK with some AP). I will describe my setups:

#1, CP510 in client mode, it works with some AP, it doesn't work with another ones

This was my 1st configuration, and it was working OK until I have to connect to another external AP/router.

computers (192.168.2.0/24) --> internal AP (RS200, AP mode) --> My router (TL-470T+, LAN=192.168.2.1, WAN=192.168.0.249 or dynamic) --> My Anthena (CPE510, Client mode, IP=192.168.0.250 or dynamic) --> external AP/router (192.168.0.1)

#2, CPE510 in AP Client router

When configuration #1 failed I used this one (it's not the best because I have a double router, but it worked Ok until I switched to another external AP/router)

computers (192.168.2.0/24) --> internal AP (RS200, AP mode) --> My router (TL-470T+, LAN=192.168.2.1, WAN=192.168.1.249 or dynamic) --> My Anthena (CPE510, AP client router mode, LAN=192.168.1.250, WAN=192.168.0.250 or dynamic) --> external AP/router (192.168.0.1)

In any case, depending on the selected external AP/router, both configurations can work or not. As I noted in my previous post, my phones or computers can connect without any issue to all the external AP/routers. What is more, when I have a problem with an external AP/router, I replace my CPE510 anthena (in #1 or #2) with an old AP (TL-WA501G) configured in Client mode, and both configuration works OK.

To sum-up:

The problem is in CPE510, I don't know why, but for some unknow reason the external AP/router ignores the connected CPE510 (ping or traceroute from the CPE510 web console dont work). If I connect to the external AP/router with my computer, I can't see the CPE510 in the network with something like the following:

$ sudo nmap -sn 192.168.0.0/24

  @Ajcvzj 

Could that be the wireless channel issue? I notice that CPE510 only supports limited channels. Even different region CPE510(like EU ver. and US ver.) can not work with each other.

Have you checked the external AP 5Ghz channels? I have a US version CPE510 and it only work with channel 149-165, and it won't work with my home router. My router is using channel 36-48 limited.