Bridging with 2xN66U's

I've got an interesting setup I'm trying to achieve.

I have one building with an existing switched network on the 192.168.5.0 subnet. Has DHCP, internet and some other services.

I need to bridge a small 15 foot gap between buildings with concrete walls.

I decided to setup a N66U router over there with its own subnet 192.168.6.0 and its own internet connections. Then another N66U back in the first building with its WAN port on the existing network and a static address.

Here is what I setup.
Building B: (routerB)
WAN: settings provided by ISP
LAN: 192.168.6.1/24
StaticRoute: 192.168.5.0/24 gateway: 192.168.6.25

Building A: (routerA)
WAN: 192.168.5.26/24 gateway: 192.168.5.1
LAN: 192.168.6.25/24

I originally had it setup with WDS, but found it difficult to maintain the connection and ended up installing TomatoShibby on the router in BuildingA so that I could use wireless client mode.

Now I have 2 major problems.
#1, wireless client mode 'seems' to work with routerB showing the signal strength in the status page. However I cannot ping or connect over http between the two networks. And routerA doesn't show up as a client on routerB.

#2, even when connected over ethernet on routerA I cannot ping or use services in the 192.168.5.0 subnet.

I seem to have lost the NAT option the stock ASUS firmware had that I used to originally accomplish this. So I'm not sure what is going on now.

Any advice? What would be the preferred way of setting this kind of wireless bridge up?