Wireless to Ethernet via WDS function

Are you sure WDS is really what you need? Based on your diagram, it looks like the Dynalink should act as a client bridge, not a WDS bridge. You may have better success with this method. The stock firmware on the Dynalink may not support client bridge mode, so consider a third-party firmware like DD-WRT or OpenWRT.

As Dagelf mentions, WDS between different vendors is usually broken.

What might work for you is flashing openWRT to your tp-link router and using the dynalink on your lan border (i.e. where you currently have the tp-link): http://wiki.openwrt.org/toh/tp-link/tl-wr740n

And use the tp-link as your wireless bridge using pseudobridge with relayd (google it, I don't have enough reputation for another link)

Although I found a simple routed client easier to setup and more stable, YMMV: http://wiki.openwrt.org/doc/recipes/routedclient

On the downside, it's less transparent and breaks any lan service that depends on broadcast.

Basically what you do is create a separate subnetwork for your bridged hosts. The tp-link connects via wireless to the dynalink, and acts as gateway for the ethernet clients. You can either do masquerading or not for this subnetwork.

If you don't masquerade, you have to make sure that the dynalink has a route back to the new subnetwork and that it does nat for it as well. Not all home routers support this.

I have the exact same setup I described and it works like a charm.