I have the same "issue" with the preview option for my posts/responses. All I can see is one line (barely). Looked around my profile but can't see where/how that would be adjusted. Did you figure it out yet?
I seem to have done something to my ability to preview posts. When I click on the preview button, all I get is a dialog box that shows a single line of text with up and down arrows on the side. I can scroll through the preview via the arrows, but I can't see the whole thing at once.
Also, how do you create a signature for your posts? I see lots of people with references to their book or wip in their signature. Is there a way to do that so that it automatically comes up when you post?