I'm not sure I can help more than this, really, so it's probably best to wait for staff to respond after the weekend (or before if any are working). Most of the people who respond to questions on these forums are, like myself, volunteers, so unless there's someone actually online at the time who knows the exact problem, generally you've just got to wait.
Other than that, two things:
You could try doing a search on Google, just in case someone has reported a similar problem and found a solution to it. This gives faster results than searching on the forums themselves. Put this into Google search (with the spaces, colons and double quotes where I've put them):-
site:en.forums.wordpress.com "put your keyword or phrase here"
and put anything you can think of that relates to the problem, into the double quotes. if you need to add more, leave a space and then add it in another pair of double quotes. That should bring up relevant posts in the forum. Alternatively, use
site:wordpress.com to search the whole site, and/or put "wordpress.com" to search only for results applicable to blogs here.
The other thing I wanted to say is this: if your main reason for wanting to use trackbacks is to bring in traffic to your blog, then there are better ways to do it as not everyone will click a trackback anyway (some people think it's spam or blogs self-advertising themselves). I have an archive of posts I did on a previous blog that are designed for people who want to attract more readers, that you might find useful:
http://blogginghelpfornewbies.wordpress.com/