How to configure multi-routing on wl500g (or wl530g) via Web interface?

I would like to access 3 or 4 subnets no DHCP, from 1 subnet in DHCP on wlan itf (and if possible lan).

Wlan Subnet: 192.168.1.t (DHCP), wl500g IP t=1

From the ethernet cable 1, are reachable:
-Subnet A: A.x/27 10.0.0.x/27
-Subnet B: B.y/27 10.0.1.y/27 maybe B', B"
-Subnet C: C.z/20 10.1.z/20 maybe C', C"

From cable 2,
-Subnet D: D.r/27 223.254.254.r/27

A,B,C have internal routes (A<->B, A<->B<->C)
If you have a IP within A, you can access A, but not B.
If you have a IP within B, you can access B and C.

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History:
Before this, i used multi-IP fixed from PC ethernet card to do this task, i just configured wl500g in hub mode (layer1).
But i would like to share, and it is not optimal to use a lot of fixed IPs for each PC.

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First idea:
I put
- cable 1 in WAN with IP fix in Subnet A: A.s/13 (netmask to allow access to B and C).
- cable 2 in LAN
Access to A ok, but nok to B, C and D.

I tried to add Static Routes without success:
network/host netmask gateway metric interface
B.y 255.255.255.224 A.s 1 WAN
C.z 255.255.255.224 A.s 1 WAN
D.r 255.255.255.224 192.168.1.1 1 LAN
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I am out of more ideas
Please, what are your ideas to configure wl500g ?