On the Connections tab, there are two add buttons and a textfield beside each.

If you just want to manually use connect1.limewire.com this one time to connect, then type it into the upper textfield and hit the add button.

If you always want to use connect1.limewire.com for connecting, type it into the lower textfield, click the add button and then click connect.

Assuming that your connect button is working (you may need to wait a little and try again), that should work.

-greg