For some reason QA nodes have an author_user of "QandAEditors" instead of the handle of the person who actually posted. This is dealt with differently on different pages, which leads to the inconsistancies that you've noticed.
The XML interface can help you verify this: View the source on this query to see the data for a normal node posted by you. Notice that you are the author_user. Compare that to the info for a Q&A post where the author_user is "QandAEditors" instead of an actual username.
Are you posting in the right place? Check out Where do I post X? to know for sure.
Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
<code> <a> <b> <big>
<blockquote> <br /> <dd>
<dl> <dt> <em> <font>
<h1> <h2> <h3> <h4>
<h5> <h6> <hr /> <i>
<li> <nbsp> <ol> <p>
<small> <strike> <strong>
<sub> <sup> <table>
<td> <th> <tr> <tt>
Snippets of code should be wrapped in
<code> tags not
<pre> tags. In fact, <pre>
tags should generally be avoided. If they must
be used, extreme care should be
taken to ensure that their contents do not
have long lines (<70 chars), in order to prevent
horizontal scrolling (and possible janitor
Want more info? How to link
or How to display code and escape characters
are good places to start.