Linksys Access Point :: WET610N Range And Signal Strength?

I'm trying to use the WET610N as a sort of access point/range extender for a single device, a remote monitoring system installed in a barn. It records temperature, power use, etc, and reports it to the internet. The barn is about 250 feet from the house where the wireless router is installed. There will be very little data flowing over the link.Setup on the WET610N went fine, and it saw the remote router at 10% strength and connected to it fine. However, when I attempt to get Status, the screen shows the headings on the left and no data on the right. Attempting to access the internet through the link on my MacBook Pro failed.