Tomato WDS second network sharing internet connection from first?

[vmachine]

I'm relatively new to networking but I know what I need and I'm about halfway there. My goal is to have a second network based on two ASUS N12 routers with Tomato installed using WDS. I have successfully got the two routers to see eachother both set to WDS+AP mode in Tomato. But I can't figure out how to get this WDS subnetwork to access the existing internet connection on another router in a different subnet. The router in the first existing network is connected to a cable modem and I have one of it's LAN ports connected to the WAN port of the first (192.168.2.1) router in the second network (192.168.2.x). The attached image should explain the setup.

From what I've read so far, I think I might need to maybe setup a static connection from router 2 to router 1 across different subnets to get the internet connection to travel from the existing network into the new WDS network. Something about assigning routing?? I've only been doing this network stuff for a few weeks so any clear and detailed explanation on getting an internet connection into a separate subnet using WDS would be very helpful for me. Also, if this involves subnet masks or DNS, please help me to know what these things mean because I don't understand them.

BTW, I'm doing this setup to add the best possible network for home theatre equipment using an existing internet connection but on a completely separate internal network. The devices on the second network will be wireless and wired with a mix of static IP and dhcp. I've already got this working using multiple subnets with the third router running DD-WRT repeater mode, but I would like to have everything on the second network all in the same subnet similar to a bridge.

 

[vmachine]

I just made a little progress on this. I was thinking that the second network (WDS) would have it's own SSID but I guess this isn't the case. I changed the SSID of router 2 and 3 to the same SSID and WPA as the first router with the internet connection. Now I am able to get internet wirelessly on the WDS network (192.168.2.x).

Still, I can't get wired internet access through the third router (192.168.2.2). Also, is there a way to control on the hardware device (currently a laptop) which subnet I get wireless internet from? Now that there's just one SSID for both subnets, this seems like a necessity. My laptop right now is defaulting to the WDS subnet for it's wireless internet connection which is good, but I need to know how to set this permanently for all devices that will be on the second (WDS) subnet.