Mike,
To add a link, use the ADD REPLY button.
When typing the message, get to the place you want to insert the link, then click the http button - first one in the line above the message window, then key or paste in the URL. Press OK
Then enter the expression you want - like CLICK HERE and OK again.
That's it!
Ostraco
PS - you can't do this from the Fast reply link, only the Add reply one