I've noticed a similar issue when using the "code" markup. if you add the closing tag directly after the markupped texted (ie, not on a new line), whatever comes after the section in markup butts up right under it (no new lines) and it makes things a bit difficult to read.
Ugh... and why is there a file upload form on the post screen if attachements are turned off? Very annoying. It seems that the "Gossamer Forum" Forums are the only ones that have it turned on.